Wall Element System and Method and Apparatus for Constructing Shoring Walls

ABSTRACT

A caisson or casing  107  for installing a sheet  102/103  into a ground or underwater location, the caisson  107  having a shaped wall  107.1 , which is open for a predetermined length and is adapted to receive and connect to an excavation means  3  within the confines of the caisson or casing  107 . In at least one embodiment, the system includes a drilling assembly  3  for insertion of a caisson or casing  1 , the drilling assembly  3  having one or more expanding drill bits  4  which are adapted to be driven by a drilling or rotation motive device  5 , the expanding drill bits  4  being adapted to be arranged with respect to the caisson or casing  1  in use, so as form a hole or bore which substantially conforms to, or substantially overlaps with, the shape of the caisson or casing  1.

I. FIELD OF THE INVENTION

The present invention relates to placement of pile or wall elements toconstruct shoring walls in difficult ground or ground conditions on landor under water.

II. BACKGROUND OF THE INVENTION

Shoring walls can be constructed using interconnected pile elements ofvarious types. The pile elements can be manufactured from variousmaterials such as steel, stainless steel, aluminium, glass fibrereinforced plastic, other composite materials or precast concrete. Sheetpile comes in a variety of sections with a variety of clutches and ismanufactured from various materials, such as steel, stainless steel;aluminium; glass reinforced plastic or polymer, glass fibre reinforcedplastic, fibre reinforced plastic or polymer.

Various methods are currently used to construct pile walls, and thesemethods include pushing, vibrating and hammering pile elements whethersheet or panel or modular wall element into the ground. In hard ground,a mandrel or pre drilling may be required. When using glass fibrereinforced plastic (GFRP) or composite sheet or aluminium sheets thisproblem is exacerbated. When installing painted metal sheet into hardground or abrasive ground, by any of the conventional means, suchconventional means will damage the integrity of the painted coating.

All of the methods mentioned in the preceding paragraph have theirlimitations and costs. Noise and vibration can often the major limitingfactors.

Any reference herein to known prior art does not, unless the contraryindication appears, constitute an admission that such prior art iscommonly known by those skilled in the art to which the inventionrelates, at the priority date of this application.

For the purpose of this specification and claims:

a: a pile element, when constructed from material other than concretewill be referred to as “the sheet” or “a sheet” each element constructedfrom concrete will be referred to as ‘the panel” or a panel.Additionally a pile element or panel can be an open section retainingwall element, having 3 or 4 sides, and be of plastic or metal, modularor bespoke, which can also serve the function of a formwork system, forexample such as that sold under the brand TRULINE SEAWALL.

b: the means of attachment of one sheet or panel to another sheet orpanel will be referred to as “the clutch” or “a clutch”;

c: an enclosing structure used to place the sheet or panel or wallelement will be referred to as “the caisson or casing” or “a caisson orcasing”;

d: an excavation means or assembly is any means to excavate an area andincludes: rotary means such as drilling and/or reaming systems which maybe expanding and/or contracting in nature or non-expanding; rotatingmechanical lever based systems which may be expanding; swinging armreaming type systems; or non-rotary means such as jet grouter pilingsystems which operate on a grout or drilling fluid being pumped underhigh pressure to fluidize a rock bed. These excavation means can bepositioned inside or outside of the caisson or casing or modular wallelements and will sometime be referred to as “the tool” or “a tool”; and

e: if drilling and/or reaming means are contained in the tool they willbe referred to as “drill bits” or if expandable drill bits are used as“expandable bits” or “reaming elements” or “expandable reamingelements”.

By the expression “substantially conforms to” is meant a situation wherethe drilling and/or reaming whether expandable or not, simply rotatewholly within the footprint of the caisson or casing.

III. SUMMARY OF THE INVENTION

The present invention provides an insertable element, being one of anopen section retaining wall element or a formwork element or a caissonor casing for installing a pile element, such as a sheet or panel or apile wall element or an open section retaining wall element or aformwork element, into a ground or underwater location, the caissonhaving a shaped wall which is open for a predetermined length, which isadapted to receive and connect to an excavation means within theconfines of the caisson or casing.

The shaped wall can have its free sides each having a clutch, and aconnecting section which closes the insertable element and/or the shapedwall.

The connection section can have a wall portion with a mating clutch tojoin with the clutches at the wall sides of the shaped wall or theinsertable element.

The connection section can be formed from one or more wall portionshaving clutches on it or them or can also include at least one elementclutch or join formation which is adapted to engage another insertableelement or sheet or panel or open section retaining wall element orformwork element previously inserted in the ground or underwaterlocation.

The connection section can be a sheet pile, panel, open sectionretaining wall element or formwork element or is formed and/or shaped asa sheet pile, panel, open section retaining wall element or formworkelement so as to function as a sheet pile, panel, open section retainingwall element or formwork element, which is adapted, in use, to beseparable from the shaped wall.

The connection section can have at least one clutch, which is adapted toconnect to at least one clutch of the shaped wall.

The connection section can have at least one element join formation orclutch which is adapted to engage a previously inserted insertableelement, or open section retaining wall element or formwork or panel orsheet or clutch thereof.

The at least one element mating join formation or clutch on theconnection section, by being adapted to engage an insertable element oropen section retaining wall element or formwork element or panel orsheet or clutch on a one of these previously inserted in the ground orunderwater location, can be adapted to act as a guide to guide theinsertable element, and an excavation means combined therewith, asexcavation occurs.

The at least one element mating join formation or clutch can be adaptedto be located outside an excavation footprint of an excavation meanscombined with the insertable element.

A releasable locking mechanism can interconnect the connection sectionand the shaped wall or the insertable element.

The locking mechanism can include one of the following: a pin passingthrough mating clutches on the shaped wall or insertable element and theconnections section which can be removed when needed; one of theconnection section or the shaped wall or the insertable element includesa flange portion provided to receive a removable pin; a bolt or a wedgeor any other mechanical attachment or binding mechanism can be used tolock them together.

The insertable element when combined with an excavation means can beadapted to allow the excavation means to provide an excavation footprintwhich can overlap an excavation footprint related to the insertableelement or a sheet or panel or a pile wall element or an open sectionretaining wall element or a formwork element previously inserted in theground or underwater location.

After the insertable element has been positioned in the ground orunderwater location, the connection section can be separable from theshaped wall or insertable element.

The shaped wall or insertable element can be adapted so that a sheet orpanel or a pile wall element or an open section retaining wall elementor a formwork element can be made to engage the clutch or join formationof a previous sheet or panel or a pile wall element or an open sectionretaining wall element or a formwork element, and pushed or hammered orvibrated into position.

The shaped wall or insertable element can be removeable from the groundor the underwater location, after the sheet pile or panel or opensection retaining wall element or formwork element is positioned, theinsertable element being a caisson or casing.

The present invention also provides the insertable element as describedabove in combination with an excavation means.

The excavation means can be a drilling and/or assembly having one ormore drilling bits and/or reaming elements which are adapted to bedriven by a drilling or rotation motive device, the drilling bits and/orreaming elements can be adapted to be arranged with respect to theinsertable element in use, so as form a hole or bore or excavation whichsubstantially conforms to or substantially overlaps with, the shape ofthe insertable element.

The one or more drilling bits and/or reaming elements can be adapted tobe positioned ahead of a leading edge of the insertable element, or arepositioned so as to excavate from within the confines of the insertableelement.

The drilling bits and/or reaming elements can be one of the following:expanding drilling bits; non-expanding drill bits; expanding reamingelements; non-expanding reaming elements.

The excavation means and/or caisson or casing can allow the excavationmeans to be withdrawn from the caisson or casing.

The excavation means can have one or more of the following features:when in an expanded condition, engages ground beyond part or all of aleading edge of the insertable element; when in the unexpanded orretracted condition remains inside the insertable element opening oropening footprint; when the excavation means is not an expandingexcavation means, it remains inside the insertable element opening oropening footprint.

The drilling bits and/or reaming elements can be rotated by at least onemotor located within the insertable element.

The drilling bits and/or reaming elements can be rotated by at least onemotor located outside the insertable element.

The drilling bits and/or reaming elements can be rotated by othermechanical means whether individually or in unison.

The excavation means can be mounted for being pulled towards or pushedaway from the insertable element.

The excavation means can be provided with a means of flushing by air,liquid, slurry, mud or a combination of any two or more of these or allof these.

Part of the excavation means can be adapted to be positioned ahead of aleading edge of the insertable element.

The excavation means can be adapted to be attached to the insertableelement.

The excavation means can be releasably attachable to the insertableelement.

The insertable element can be constructed from two or more sections.

The excavation means can substantially close off an opening formed by aninner periphery of the insertable element.

The excavation means can be one or more excavation means are used forthe opening.

The excavation means can excavates hard ground or drills and/or reamshard ground, allowing the insertable element to be positioned to apredetermined or required depth.

There can be a spacing or gap between an interior surface of theinsertable element and a body of the excavation means.

The spacing or gap can be of the order of 2 to 10 millimeters, or morepreferably of the order of 2 mm to 5 mm.

The connection section can be unconnected to excavation means to beassociated with the insertable element.

The excavation means to be associated with the insertable element, isconnected to or is a releasable part of the shaped wall or insertableelement.

The present invention also provides a method of inserting an insertableelement being one of an open section retaining wall element or aformwork element or a caisson or casing for installing a pile element,such as a sheet or panel or a pile wall element or an open sectionretaining wall element or a formwork, or a sheet pile or panel or opensection retaining wall element or a formwork system or element of such aformwork system installed via a caisson or casing, the method including:providing an insertable element or a pile element, such as a sheet orpanel or a pile wall element or an open section retaining wall elementor a formwork, providing an excavation means which is expandable toexcavate outside or within the confines of the insertable element andwithdrawable from the confines of the insertable element; utilizing anearlier installed insertable element or pile element as an excavation ordrilling and/or reaming guide or if the insertable element is open,overlapping the excavation area of the new insertable element or pileelement with that of an earlier installed insertable element or pileelement.

The method can include use of a connection section to engage theinsertable element or the pile element.

The connection section can enable the insertable element or the pileelement to be guided by the earlier installed insertable element or thepile element.

The connection section can also act as a sheet pile or panel or opensection retaining wall element or formwork element and remains in theground or underwater location.

The present invention also provides an excavation means for use with aninsertable element being one of an open section retaining wall elementor a formwork element or a caisson or casing for installing a pileelement, such as a sheet or panel or a pile wall element or an opensection retaining wall element or a formwork, or a sheet pile or panelor open section retaining wall element or a formwork system or elementof such a formwork system installed via a caisson or casing so as toexcavate in front of the leading edge of insertable element or the pileelement, the excavation means having a body to mount at least oneexcavation tool so that the at least one excavation tool is spaced froma wall of the insertable element or the pile element, or if multipletools are present they are spaced from each other so that the outsidediameter of the at least one excavation of the tools are spaced fromeach other.

The excavation means can include a detachable connection to aninsertable element or the pile element with which it will be used.

The excavation means can be one of a jet grouter; a drilling tool; areaming tool; a drilling and/or reaming tool; or drilling and/or reamingtool assembly.

The excavation means can include expandable drilling and/or reaming bitsor portions.

The present invention also provides a method of excavation for aninsertable element being one of an open section retaining wall elementor a formwork element or a caisson or casing for installing a pileelement, such as a sheet or panel or a pile wall element or an opensection retaining wall element or a formwork, or a sheet pile or panelor open section retaining wall element or a formwork system or elementof such a formwork system installed via a caisson or casing, the methodincluding the steps of: providing a an insertable element or pileelement; attaching to the insertable element or a pile element anexcavation means as described above; advancing the excavation means toexcavate ground beneath the excavation means until the insertableelement or pile element engages hard ground or is otherwise at asufficient depth; detaching the excavation means from insertable elementor pile element excavating ahead of insertable element or pile elementto a predetermined depth; withdrawing the excavation means frominsertable element or pile element; repeating as many times as needed tosituate the insertable element or pile element until a desired length ofshoring wall is achieved.

The present invention also provides an excavation means and aninsertable element being one of an open section retaining wall elementor a formwork element or a caisson or casing for installing a pileelement, such as a sheet or panel or a pile wall element or an opensection retaining wall element or a formwork, for insertion into ground,the excavation means being able to excavate inside the opening oropening footprint of the insertable element, the excavation means havinga body to mount at least one excavation tool so that overlappingexcavations will result.

The excavation means can include a detachable connection to theinsertable element.

There can be at least one excavation tool, which in the case of one toolis spaced from an end wall of the insertable element, and in the case ofmore than one tool are spaced from each other so that the outsidediameter of excavation of the tools are spaced from each other so thatwhen the body is rotated through 180 degrees, the excavation that occursproduces an overlapped excavation footprint, so as to provide a mirrorreverse excavation footprint.

The excavation means can be one of: a jet grouter; one or more drillingtools; a drilling tool assembly; a drilling and/or reaming tool; or areaming tool.

The excavation means can includes: only expandable drilling and/orreaming bits; or only non-expanding drill bits; or a combination ofexpanding and non-expanding where the expanding drill or reaming bitswhen expanded have the same or a greater outside diameter as thenon-expanding drill bits.

The present invention also provides a method of excavating ground,either above or under water, for insertion of an insertable elementbeing one of an open section retaining wall element or a formworkelement or a caisson or casing for installing a pile element, such as asheet or panel or a pile wall element or an open section retaining wallelement or a formwork, the method including the steps of: providing aninsertable element and an excavation means or assembly as describedabove; activating the excavation means to excavate ground beneath theexcavation means so as to produce an excavation or a series ofoverlapped excavations outside of or within the opening or openingfootprint of the insertable element.

The present invention further provides a drilling and/or reamingassembly for insertion of an insertable element being one of an opensection retaining wall element or a formwork element or a caisson orcasing for installing a pile element, such as a sheet or panel or a pilewall element or an open section retaining wall element or a formwork, ora sheet pile or panel or open section retaining wall element or aformwork system or element of such a formwork system installed via acaisson or casing, the drilling and/or reaming assembly having one ormore drilling and/or reaming bits which are adapted to be driven by adrilling or rotation motive device, the drill and/or reaming bits beingadapted to be arranged with respect to the insertable element, so asform a hole or bore into which can be inserted the insertable element.

The drilling and/or reaming bits can be adapted to be positioned aheadof a leading edge of the insertable element.

The drilling and/or reaming bits can be expanding drilling and/orreaming bits.

The expanding drill and/or reaming bits when in a retracted condition,can allow the drilling and/or reaming assembly to be inserted intoand/or withdrawn from the insertable element.

The expanding drilling and/or reaming bits, when in an expandedcondition, can have ground engaging bits or portions extending beyondpart of a leading edge of the insertable element.

The drilling and/or reaming bits can be rotated by a motor locatedwithin the insertable element.

The drilling and/or reaming bits can be rotated by motor means locatedoutside the insertable element.

The drilling and/or reaming bits can be rotated by other mechanicalmeans whether individually or in unison.

The drilling and/or reaming assembly can be mounted for being pulledtowards or pushed away from the insertable element.

The drilling and/or reaming assembly can be provided with a means offlushing which has one or more of the following features: flushing byair, liquid, slurry, mud or a combination of two or more of these or allof these; is delivered at a pressure of the order of 50 psi to 500 psi;exits the drilling and/or reaming assembly in a horizontal directionfrom the drilling and/or reaming assembly when it is vertical; exits thedrilling and/or reaming assembly at approximately 90 degrees to thelongitudinal axis of the drilling and/or reaming assembly.

The one or more drilling and/or reaming bits can be adapted to bepositioned ahead of a leading edge of the insertable element.

The drilling and/or reaming assembly can be adapted to be attached tothe insertable element.

The drilling and/or reaming assembly can be releasably attachable to theinsertable element.

The insertable element does not rotate as it advances downwardly.

The insertable element can have at least one first clutch on one side soas to engage a mating shaped clutch on a previously installed insertableelement.

The insertable element can have one of the following: two clutches onone side; or two clutches on one side and two clutches on an oppositeside.

The insertable element can be constructed from two or more sections.

The insertable element can be such that the at least one element matingjoin formation or clutch on the connection section is at least two suchelement mating join formations or clutches.

The connection section can have at least two element mating joinformation or clutches.

The drilling assembly can substantially close off an opening formed byan inner periphery of the insertable element.

Multiple drilling and/or reaming bits or heads can be used for eachopening.

The drilling and/or reaming assembly can disturb, plasticize, fluidize,or worry a bed drilled and/or reamed by the drilling and/or reamingassembly, allowing the insertable element to be positioned to apredetermined or required depth.

There can be a spacing or gap between an interior surface of theinsertable element and a body of the drilling and/or reaming assembly.

The spacing or gap is of the order of 2 to 10 millimeters but is mostpreferred to be of the order of 2 mm to 5 mm.

The excavation means can include at least one reaming portion which isformed from a section or length of cable or spring steel or anarticulated ground engaging member.

The excavation means can include a flushing passage which discharges ina direction at approximately 90 degrees to the longitudinal axis of theexcavation means or the axis of rotation of the excavation means.

The excavation means can include a flushing fluid system or drillingfluid system which operates to pump drilling fluid from the excavationmeans or a portion there of, at a pressure of the order of 50 psi to 500psi.

The excavation means can include a shaped body or shaped guides whichlocate the excavation means to excavate relative to or along apre-determined axis, which axis is located at an off-centre locationrelative to the footprint of the caisson or casing or open sectionretaining wall element or element of a formwork system.

The off-centre location can provide the extremities of a locus orrotation envelope or excavation which clear the clutches of a previouslyinstalled caisson or casing or open section retaining wall element orelement of a formwork system, and which locus or rotation envelope orexcavation extends past the forward or opposite side clutches of thecaisson or casing or open section retaining wall element or element of aformwork system being installed.

The excavation means can include a segmented construction allowing theassembly to be increased or decreased in length to suit differentlengths of the caisson or casing or open section retaining wall elementor element of a formwork system being installed.

The excavation means can be one of: a jet grouting tool; a drillingtool; a reaming tool; a drilling and reaming tool.

The present invention also provides a method of inserting a caisson orcasing or open section retaining wall element or element of a formworksystem into a friable terrain, the method including the steps of:arranging a drilling and/or reaming assembly as described above, withrespect to a caisson or casing or open section retaining wall element orelement of a formwork system; positioning the drilling assembly and thecaisson or casing or open section retaining wall element or element of aformwork system over a location for insertion of the caisson or casingor open section retaining wall element or element of a formwork system;operating the drilling assembly from another location, until the caissonor casing or open section retaining wall element or element of aformwork system has been situated as desired.

The method can also include the steps of: retracting the expanding bitsand/or reamers, and withdrawing the drilling and/or assembly from thecaisson or casing or open section retaining wall element or element of aformwork system.

The method can also include the step of inserting or forming astructural element into the caisson or casing or open section retainingwall element or element of a formwork system.

The method can include the step of withdrawing the caisson or casing oropen section retaining wall element or element of a formwork system.

The structural element can include a through aperture via which grout isreceived to grout the structural element.

The method can further include the step of separately drilling orreaming a hole into a hard ground at a position which corresponds withthe through aperture.

The through aperture can be adapted to receive a reinforcing dowel.

The method can include the step of repeating the method to insertfurther structural elements.

The method can further include grouting spaces between adjacentstructural elements.

The lateral vertical sides of the structural elements can be shaped sothat the grout between adjacent structural elements forms a grout key.

A stocking made from canvas, plastic, any appropriate nylon, orgeo-fabric can be placed over a grout line used to grout spaces betweenadjacent structural elements.

The method can further include the step of securing a capping beam tothe structural element or casting in situ a capping beam.

The capping beam and structural element can be bolted or screwedtogether.

The capping beam can include one or more inserted or pre-castreinforcement bars, each to be inserted into a corresponding aperture inthe structural element; or the structural element includes one or moreinserted or pre-cast reinforcement bars, whereby each reinforcement baris received by a corresponding aperture in the capping beam; or thestructural element includes one or more inserted or pre-castreinforcement elements, and the capping beam is cast onto the structuralelement and around the reinforcement elements.

The method can include securing an anchoring tie in the capping beam.

The method can include the step of attaching a subsequent caisson orcasing or open section retaining wall element or element of a formworksystem to the caisson or casing or open section retaining wall elementor element of a formwork system.

The present invention also provides a retaining wall element for use incontrolling land erosion in contact with water which comprises:self-supporting polymeric or metal construction, each having a verticallongitudinal interior channel disposed therein enclosed by at leastthree sides; each of the elements having a pair of opposed faces towhich are connected one or more fastening means; each of the elementsconnected by mating engagement of the at least one fastening means onone first element with at least one fastening means on the at least onesecond element, the fastening means being an engageable clutch orJ-shaped hook; characterized in that at least one of the elementsincludes in or on at least one of a front wall and/or rear wall, anelongated fastening means allowing the at least one element to connectto the ends of a wall or walls of a casing or caisson and/or anexcavation means, which will be used to excavate and/or keep clear avolume in which the element or elements will be installed in anunderwater location.

The fastening means on the front and/or the rear wall can be anexternally arranged engageable clutch or J-shaped hook. Alternatively,the fastening means on the front and/or the rear wall is an internallyarranged engageable clutch or groove able to receive a J-shaped hook.

The wall element can further comprise at least one end cap having afastening means to attach to the element.

The wall element can be constructed by its wall formation shape and/orthickness to function as a structural wall when it is in an open and/orhollow condition.

The wall element can be initially open and/or hollow and when joined andassembled with like or similar elements, is then used as an in-situformwork and subsequently filled with concrete, cement or grout, orfilled with gravel to form a finished structural wall construction.

The present invention additionally utilizes the technology described inAustralian patent applications 2016100200, 2016203790 and internationalapplication PCT/AU2016/051201, and the text and drawings of theseapplications are incorporated herein.

IV. BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of a preferred embodiment will follow, by way ofexample only, with reference to the accompanying Figures of thedrawings, in which:

FIG. 1.1 is a side elevational view of a caisson/casing and drillingassembly with the drill bits in a retracted condition;

FIG. 1.2 is a front elevational view of the apparatus of FIG. 1.1;

FIG. 1.3 is a plan view of the apparatus of FIG. 1.1;

FIG. 2.1 is a side elevational view of a caisson/casing and drillingassembly with the drill bits in an extended or expanded condition,showing how a substantial portion of the periphery of the caisson/casingis overlapped by the drill bits;

FIG. 2.2 is a front elevational view of the apparatus of FIG. 2.1;

FIG. 2.3 is a plan view of the apparatus of FIG. 2.1;

FIG. 3.1 is a side elevational view of a caisson/casing and drillingassembly with the drill bits in an extended or expanded condition withthe middle bit lower than the outer bits and the whole of the peripheryis overlapped by the footprint of the drill bits in extended or expandedcondition;

FIG. 3.2 is a front elevational view of the apparatus of FIG. 3.1;

FIG. 3.3 is a plan view of the apparatus of FIG. 3.1;

FIG. 4.1 is a side elevational view of a caisson/casing and drillingassembly with the drill bits in an extended or expanded condition,similar to FIGS. 3.1 to 3.3, with the middle bit being at same height asthe outer bits, but 90 degrees out of phase, and the whole of theperiphery is overlapped by the footprint of the drill bits in extendedor expanded condition;

FIG. 4.2 is a front elevational view of the apparatus of FIG. 4.1;

FIG. 4.3 is a plan view of the apparatus of FIG. 4.1;

FIG. 5 illustrates a plan view of an embodiment similar to that of FIG.2.3, where the caisson/casing has a hollow T-shape;

FIG. 6 illustrates a plan view of an embodiment similar to that of FIG.2.3 or 5, where the caisson/casing has a hollow arcuate or half roundshape;

FIG. 7 illustrates a plan view of an embodiment similar to that of FIG.2.3, 5 or 6, where the caisson/casing has is a relatively large hollowsquare shape, utilizing some 9 expanding bits;

FIG. 8.1 illustrates a side elevational view of a caisson/casing anddrilling assembly with two drill bits, both in an extended or expandedcondition;

FIG. 8.2 illustrates a plan view of the caisson/casing shown in FIG.9.1, where the caisson/casing is generally shaped like the number “8”;

FIG. 8.3 illustrates a front or rear elevational view of thecaisson/casing and drilling assembly shown in FIG. 8.1;

FIG. 8.4 illustrates a plan view of an embodiment similar to that ofFIG. 2.3, 5, 6, or 7 where the caisson/casing has the shape shown inFIG. 8.2;

FIG. 9 illustrates a vertical cross section through the embodiment ofFIGS. 1.1 to 2.3 showing the assembly of a caisson/casing and a drillingassembly with expanding drill bits which are driven by hydraulic motors;

FIG. 10 are photographs of examples of two drill bits and theirspecifications which can be utilized with the embodiments of theinvention;

FIG. 11 illustrates a dual section view of the drilling assembly and itsdisengagement and retraction mechanism;

FIG. 12 illustrates a schematic view similar to FIG. 9, except thatintervening the between the lifting assembly and latches is a hydraulicram system to push the drilling assembly downward relative to thecaisson or casing;

FIG. 13.1 is a front or rear view of a plurality of structural panels,drilling assembly, and grout between the panels;

FIG. 13.2 is plan view of the panels of the apparatus of FIG. 13.1;

FIG. 13.3 is a cross section through line 1-1 of FIG. 13.2;

FIG. 14.1 is a schematic front view of a plurality of structural panelsshowing toe grouting of some of the panels;

FIG. 14.2 is a schematic plan view of FIG. 14.1;

FIG. 14.3 is a cross section through line 2-2 of FIG. 14.1;

FIG. 15.1 is a schematic cross sectional view of a plurality ofstructural panels being attached to rock or hard ground;

FIG. 15.2 is a plan view of FIG. 15.1;

FIG. 15.3 is a cross section through line 3-3 of FIG. 15.2;

FIG. 16.1 is a schematic cross sectional view of a plurality ofstructural panels and a capping beam attached to some of the panels;

FIG. 16.2 is a schematic plan view of FIG. 16.1;

FIG. 16.3 is a cross section taken through line 4-4 of FIG. 16.2;

FIG. 16.4 depicts an alternative embodiment for attaching dowels and apre-cast capping beam to a panel;

FIG. 16.5 depicts an alternative embodiment for a capping beam to apanel;

FIG. 16.6 depicts another alternative embodiment for attaching thecapping beam to a panel;

FIG. 17.1 is a front view of two caissons in situ, one of which showingreinforcement bars;

FIG. 17.2 is a plan view of FIG. 17.1, schematically showing concretepoured into the caisson as formwork;

FIGS. 18.1 and 18.2 are schematics depicting a capping beam with landanchors or ties attached;

FIG. 19.1 is a schematic depicting the initial positions of a drillingassembly and a caisson on a friable bed, preferably under water;

FIG. 19.2 is a schematic depicting the movement of plasticised ordisturbed bed matter;

FIG. 19.3 is a schematic depicting the upward movement and accumulationof plasticised bed matter as the caisson sinks;

FIG. 19.4 is a schematic depicting the downward movement of plasticisedbed matter once the caisson is removed;

FIGS. 20.1 to 20.8 are cross sections showing the method where by acaisson inserted into a hole formed by the drill assembly, and a secondcaisson is attached and inserted into the hole;

FIG. 21 is a schematic view of a caisson which can be verticallyattached to another caisson;

FIG. 22 is a schematic view of a caisson which can be lowered by theapplication of pulling forces.

FIG. 23 is a schematic plan view of three sheets of a Larsson type 755sheet pile wall showing the form and nature of the clutch;

FIG. 24 is a schematic plan view of a caisson and drilling tool attachedto a first section of sheet pile already positioned;

FIG. 24A is a schematic plan view of a pin or linkage system toreleasably connect the caisson and connections section of FIG. 24;

FIG. 25 is a schematic plan view of the caisson and tool of FIG. 24 withthe connecting section removed and the expandable bits contracted;

FIG. 26 is a schematic plan view of the caisson of FIG. 25 with the toolremoved;

FIG. 27 is a schematic plan view of the caisson of FIG. 26 with thesecond sheet attached to the first;

FIG. 28 is a schematic plan view of the first and second sheets of FIG.26 with the caisson removed;

FIG. 29 is a schematic plan view of a caisson and drilling tool attachedto the second sheet of FIG. 28;

FIG. 30 is a schematic plan view of the caisson and a first sheet;

FIG. 30A is a schematic plan view of a pin or linkage system toreleasably connect the caisson and connections section of FIG. 30;

FIG. 31 is a schematic plan view of two sheets connected by a cut tosize bespoke joining sheet;

FIG. 32 is a schematic plan view of a first shape of caisson;

FIG. 33 is a schematic plan view of a second shape of caisson;

FIG. 34 is a schematic plan view of a third shape of caisson;

FIG. 35 is a schematic front elevation of a sheet pile wall;

FIG. 36 is an end elevation of a caisson constructing a sheet pile wall;

FIG. 37 is an end elevation of a sheet pile wall.

FIG. 38 is a plan view of another caisson and drilling assembly with asheet pile releasably forming a part of the caisson;

FIG. 39 is a schematic plan view of a pin or linkage system toreleasably connect the caisson and sheet pile section at the left sideof the assembly of FIG. 38;

FIG. 40 is a schematic plan view of a pin or linkage system toreleasably connect the caisson and sheet pile section at the right sideof the assembly of FIG. 38;

FIG. 41 is caisson and drilling assembly which has two drill elements,which are able to be repositioned within the caisson or casing;

FIG. 42 is the assembly of FIG. 41, showing the drilling effect when thetwo drill elements are re-positioned within the caisson or casing;

FIG. 43 is the assembly of FIG. 41 in a schematic cross sectional viewwith the drill assembly being moved through the caisson before reachingits drilling position, with the drill bits retracted;

FIG. 44 is a plan view of the assembly of FIG. 43;

FIG. 45 is the assembly of FIGS. 43 and 44, in a schematic crosssectional view with the drill assembly being in its drilling position,with the drill bits extended;

FIG. 46 is a plan view of the assembly of FIG. 45 showing the diameterof the bores drilled and/or of the radial reach of the drill bits whenextended;

FIG. 47 is the assembly of FIGS. 43 and 44, in a schematic crosssectional view with the drill assembly being in its drilling positionafter having been re-positioned, with the drill bits extended;

FIG. 48 is a plan view of the assembly of FIG. 47 showing the perimeterof the bores drilled by assembly in FIG. 47 and previously drilled bythe assembly in FIG. 45;

FIG. 49 is the assembly of FIGS. 43 and 44, in a schematic crosssectional view with the drill assembly being retracted from its drillingposition of FIG. 47, with the drill bits retracted and caisson advanced;

FIG. 50 is a plan view of the assembly of FIG. 49 showing the diameterof the drill bits within the confines of the caisson;

FIG. 50A illustrates a schematic plan view of another connection sectionor piece;

FIG. 51 illustrates a schematic front elevation of a first sheet pileplaced to required depth and a second sheet pile attached to the firstsheet pile and driven to the top of a hard seabed;

FIG. 52 illustrates a side elevation of the apparatus of FIG. 51;

FIG. 53 illustrates a side elevation of the second sheet pile with thecombined excavation assembly and caisson or casing attached and with thebits collapsed drilled to the top of the hard seabed;

FIG. 54 illustrates the drill bits extended below the second sheet pile;

FIG. 55 illustrates the second sheet pile after being drilled into theseabed;

FIG. 56 illustrates the combined excavation assembly and caisson orcasing removed leaving the second sheet pile in place;

FIG. 57 illustrates the second sheet pile grouted in place and the softseabed backfilled up to ground level.

FIG. 58 illustrates a schematic front elevation of a first installedsheet pile with a second sheet pile with caisson or casing andexcavation assembly, shortly after the sliding connection of theclutches between the first and second sheet;

FIG. 59 illustrates a side view of only the second sheet pile andcombined caisson or casing and excavation assembly with drill bits inexpanded state;

FIG. 60 illustrates the second sheet pile and combined caisson or casingand excavation assembly with drill bits in expanded state of FIG. 59,drilled into hard ground;

FIG. 61 Illustrates the unlocking of the drill assembly and shaped wallfrom the sheet pile and sliding same up the sheet pile;

FIG. 62 illustrates the sheet piled of FIGS. 58 to 61 grouted in placeand land back filled to upper lip of the sheet pile;

FIG. 63 illustrates a caisson (which extends to above water level orsoft bed level) and non-expanding drilling assembly, prior to entry intowater;

FIG. 64 illustrates the assembly of FIG. 63 sunk or pushed or drilledthrough soft bed material to hard rock bed, and drilling within confinesof caisson just beginning drilling into hard ground;

FIG. 65 illustrates the assembly of FIG. 64, with the drill assemblydown to depth;

FIG. 66 illustrates the withdrawal of the drilling assembly from thecaisson;

FIG. 67 illustrates the placement of the second sheet;

FIG. 68 illustrates the grouting and backfill of the second sheet ofFIG. 67;

FIG. 69 illustrates the caisson or casing and non-expandable drillingassembly, with a curved connection section;

FIG. 70 illustrates the assembly of FIG. 69 with connection section anddrill assembly withdrawn or removed and corresponds to FIG. 66;

FIG. 71 illustrates the placement of the second sheet inside caisson andcorresponds to FIG. 67;

FIG. 72 illustrates the second sheet connected to the first sheet withthe caisson removed and corresponds to FIG. 67, but is prior to groutingand back filling;

FIG. 73 illustrates the caisson and drilling assembly arrangementconnected to the second sheet for guidance to drill for the third sheetpile;

FIG. 74 illustrates a schematic plan view of the first second and thirdsheet piles in grouted overlapping excavations;

FIG. 75 illustrates a schematic plan view of a caisson or casing andexcavation footprint for use with interconnecting concrete panels;

FIG. 76 Illustrates a schematic plan view of a connection section foruse with the system of FIG. 75;

FIG. 77 illustrates a schematic plan view of another caisson or casingand excavation footprint for use with interconnecting concrete panelswith the caisson or casing using the earlier positioned panel forguidance;

FIG. 78 illustrates a schematic plan view of further caisson or casingand excavation footprint for use with interconnecting concrete panelswith the caisson or casing interacting with the earlier positioned panelfor guidance;

FIG. 79 illustrates a schematic plan view of further caisson or casingand non-expanding drill bit excavation footprint for use withnon-interconnecting concrete panels with the caisson or casinginteracting with the earlier positioned panel for guidance;

FIG. 80 illustrates side view of the caisson and drilling assembly ofFIG. 79, showing the non-expanding drill bits;

FIG. 81 illustrates a schematic plan view of the placement of a secondconcrete panel into the caisson and the excavation footprint, before thecaisson or casing is removed but after drill assembly has been removed;

FIG. 82 illustrates a schematic plan view showing the first and secondconcrete panels in place in the excavation footprint;

FIG. 83 is a schematic plan view of a caisson or casing with a drillingassembly with four expandable bits, which when expanded are overlappingand within the footprint of the opening of the caisson or casing;

FIG. 84 illustrates a schematic side view of the of the apparatus ofFIG. 83, showing the bits in expanded condition;

FIG. 85 is a view similar to that of FIG. 84, except that the bits areshown in a contracted condition;

FIG. 86 is a schematic plan view of a caisson or casing with a drillingassembly with four non expandable bits which are overlapping and withinthe footprint of the opening of the caisson or casing;

FIG. 87 illustrates a schematic side view of the apparatus of FIG. 86,showing the bits;

FIG. 88 illustrates a plan view of the excavation foot print within theCaisson or casing, with a pre-cast concrete panel therein, as will beformed by the apparatus of either FIGS. 83 to 85 and/or 86 and/or 87.

FIG. 89 illustrates a caisson or casing and excavation means or drillingassembly which has three excavation tools or drill elements,representative of an odd number excavation tools or drill elements,which excavate wholly within the caisson or casing, which are able to berepositioned to produce an overlapping excavation footprint;

FIG. 90 illustrates a caisson or casing and excavation means or drillingassembly of FIG. 89 showing the drilling effect when the threeexcavation tools or drill elements are re-positioned within the caissonor casing;

FIG. 91 illustrates a caisson or casing and excavation means or drillingassembly which has three excavation tools or drill elements,representative of an odd number excavation tools or drill elements,which excavate within and/or outside the caisson or casing, which areable to be repositioned to produce an overlapping excavation footprint;

FIG. 92 illustrates a caisson or casing and excavation means or drillingassembly of FIG. 91 showing the drilling effect when the threeexcavation tools or drill elements are re-positioned within the caissonor casing;

FIG. 93 illustrates a caisson or casing and excavation means or drillingassembly which has one excavation tool or drill element, which excavatewholly within the caisson or casing, which is able to be repositioned toproduce an overlapping excavation footprint;

FIG. 94 illustrates a caisson or casing and excavation means or drillingassembly of FIG. 93 showing the drilling effect when the excavationtools or drill element is re-positioned within the caisson or casing;

FIG. 95 illustrates a caisson or casing and excavation means or drillingassembly which has one excavation tool or drill element, which excavateinside and/or outside the caisson or casing, which is able to berepositioned to produce an overlapping excavation footprint;

FIG. 96 illustrates a caisson or casing and excavation means or drillingassembly of FIG. 95 showing the drilling effect when the excavation toolor drill element is re-positioned within the caisson or casing;

FIG. 97 illustrates a caisson or casing and excavation means or drillingassembly of earlier Figures, which is being utilized with two modularwall element or formwork such as the TRULINE SEAWALL Modular wallsystem, so as to position such a modular wall element or if used asformwork ready to receive poured or pumped concrete or gravel.

FIG. 98 illustrates a caisson or casing being utilized with a modifiedmodular wall element or formwork;

FIG. 99 illustrates a caisson or casing being utilized with anothermodified modular wall element or formwork;

FIG. 100 illustrates a schematic cross section in side view (direction Yof FIG. 102) through a drilling and reaming apparatus cooperatingdirectly to a modular wall element of FIGS. 97 to 99;

FIG. 101 is a schematic cross sections in side view (direction Z of FIG.102) of the system of FIG. 100, where the drilling and reaming apparatushas expanded;

FIG. 102 illustrates an underneath view of the arrangement of FIG. 100,with the drill bit 4 removed for illustration purposes;

FIG. 103 illustrates an underneath view of the arrangement of FIG. 101with the drill bit 4 removed for illustration purposes;

FIG. 104 is a schematic side view cross section through a drilling andreaming apparatus as used with the drilling and reaming assembly ofFIGS. 101 and 103, showing different levels of the multiple reamingelements;

FIG. 105 is a schematic side view cross section through a drilling andreaming apparatus as used with the drilling and reaming assembly ofFIGS. 100 and 102, in the process of being withdrawn from a wallelement;

FIG. 106 illustrates a side view cross section of the drill head;

FIG. 107 illustrates a schematic plan view of the multiple equi-spacedreaming elements of the drill assembly of FIG. 104;

FIG. 108 illustrates a side sectional view of part of the drilling andreaming assembly;

FIG. 109 illustrates a plan view of the part of the off-set drilling andreaming assembly of FIG. 108;

FIG. 110 is a schematic plan view of a three sided modular wall elementinstalled in a cavity drilled by a twin drive shaft system based on thedrilling and reaming system of FIGS. 100 to 109;

FIG. 111 is a schematic plan view of a four sided modular wall elementinstalled in a cavity drilled by a twin drive shaft system based on thedrilling and reaming system of FIGS. 100 to 109;

FIG. 112 is a schematic plan view showing the geometry of a three sidedmodular wall element installed in a cavity drilled by a single drilldrilling system of FIGS. 100 to 109;

FIG. 113 is a schematic plan view of an alternative caisson or casinginteracting with a modular wall element;

FIG. 114 is a schematic front or side view of a drilling assemblycontained within a body or section, whether hollow or solid, the outsideof which is shaped to match the shape of a modular wall element; and

FIG. 115 is a schematic sectional view of the drilling assembly of FIG.114 through the section plane A-A.

V. DETAILED DESCRIPTION OF THE EMBODIMENT OR EMBODIMENTS

The description and claims relate to the use of caissons or casings, andcaissons and casings, to place structural elements into ground whileminimizing disturbance of the surrounding environment. For the purposeof this specification and attached claims, the word “caisson” is meantto describe a hollow structure, which can be pressurized, that is, ableto bear hydrostatic pressure either as water is evacuated from inside,or air is pumped in, whereas the word “casing” is meant to describe ahollow structure which is not pressurized, that is, water may be on theinside of the hollow structure. The following description applies toboth types unless it is specified otherwise.

While the following description is in respect of an unpressurisedcaisson or casing, driven vertically in marine sediment it will bereadily understood that the invention and embodiments thereof can beapplied to pressurized caissons, and in directions other than verticaland other ground types.

Illustrated in FIGS. 1.1 to 1.3 is a generally rectangular caisson orcasing 1, which can be of any desired height and/or wall thickness.Inside of the caisson or casing 1 is mounted an inner drilling assembly3 with thee drill bits 4, being in a retracted condition. Not shown inthese Figures are the attachment of the inner drilling assembly to thecaisson or casing, or the bit drive, or flushing mechanism, but they areillustrated and described in respect of FIG. 9. The drill bits 4 aremounted for rotation in the drilling assembly 3, as described later inrespect of FIG. 9. It will be noted from FIGS. 1.1, 1.2 and 1.3 that theretracted size or diameter of the drill bit 4 that is selected for usewith the caisson/casing 1, is such as to fit within the inner walldimension of the caisson/casing 1. The expansion and retraction of thecutting edges can be achieved by rotation, or by mechanical, hydraulic,or other means.

Illustrated in FIGS. 2.1 to 2.3 are a similar Figures to FIGS. 1.1 to1.3 respectively, showing the relative positioning of the caisson/casing1's wall with the drill bits 4.1 being the same as drill bits 4, exceptin an extended or expanded condition. It should be noted that the drillbits now labeled 4.1 in their extended or expanded condition do notcover the complete leading edge 2 of the caisson/casing 1, as is visiblein each of FIGS. 2.1 to 2.3. However, it will be noted that asubstantial portion of the periphery of the caisson/casing perimeter isoverlapped by the outside diameter of the extended or expanded drillbits 4.1. In soft ground or highly friable terrain, this will not hinderthe advance, downward movement or insertion of the caisson/casing 1'sinto such ground.

The caisson or casing 1 does not rotate whilst it is advanced orinserted into the ground. The terrains in which the embodiments are usedare friable ground whereby the “cuttings” or bed are disturbed orplasticized, fluidized or worried, and are displaced by the drillingassembly and/or the caisson or casing. The embodiments do not drill orfunction when rock is encountered. The cuttings in these terrains aresimply disturbed or moved away, and mixed with water by the rotationaction of the drilling bits 4, especially in e.g. a river bed. Thisenables the caisson or casing to sink into the ground and reach therequired or predetermined depth, under the influence of gravity, by apushing or a pulling force, or by hammering. For instance, as shown inFIG. 22, workers can apply a tension rather than a compressive force tolower the caisson. This can be done by pulling on a rope, cable orsimilar 38, which is arranged around pulleys 40 to transmit the pullingforce into a downward force upon the caisson or casing 1.

The drill assembly 3 effectively closes off, or substantially closesoff, the opening formed by the inner periphery at the leading ledge ofthe caisson or casing.

It will be noted from FIGS. 2.2 and 2.3, that the outside diameter ofthe expanded drill bits 4.1 do not overlap, ensuring the easy operationand obviates the need to synchronize the bits 4.1 in their cuttingaction.

As the bits 4.1 when expanded, can be contracted to the positions shownin FIGS. 1.1 to 1.3, this means that when the caisson/casing 1 is in thedesired position in the earth, river or harbour bed, or other location,once brought to the retracted condition can be withdrawn from thecaisson/casing 1, with the friction with the caisson/casing 1 outerwall, ensuring that it does not move when the drilling assembly 3 iswithdrawn from the caisson/casing 1.

Illustrated in FIGS. 3.1 to 3.3 are respectively similar views to thatof FIGS. 2.1 to 2.3 with the drill bits 4.1 and 4.2 in their extended orexpanded conditions covering the complete leading edge 2 or the wholeperiphery of the caisson/casing 1. Drill bit 4.2 is verticallypositioned lower with respect to the bits 4.1, so that the rotation ofbit 4.2 does not conflict with the rotation of other bits 4.1.Alternatively, the bit 4.2 can be positioned above other bits 4.1, inorder to achieve a similar functional effect.

Illustrated in FIGS. 4.1 to 4.3 are respectively similar illustration tothat of FIGS. 3.1 to 3.3, with the drill bits 4.3 in their extended orexpanded position, but the outer bits 4.3 being at a 90 degrees phasedifference to the inner bit 4.3. The rotation of the drill bits in thisassembly would need to be synchronized to avoid conflict orinter-engagement. The synchronization could be achieved by chains, gearsor any other appropriate means.

Illustrated in FIGS. 5, 6 and 7 are caissons 1 and inner drillingassemblies 3 of various shapes. The location of the drill bits 4.1 areas detailed in FIGS. 2.1 to 2.3. The drill bits 4.1 of FIGS. 5, 6 and 7,could also be arranged as described in FIGS. 3.1 to 3.3 or 4.1 to 4.3.

Illustrated in FIGS. 8.1 to 8.4 are a caissons/casing 1 and an innerdrilling assembly 3 of the shape which generally corresponds to thenumber “8”. Two drilling bits 4.1, 4.2 are provided in the drillingassembly 3. The drilling bits 4.1, 4.2, in their expanded conditionoverlap with each other. Therefore, one drill bit 4.2 is positionedlower than the other drill bit 4.1.

It will be readily understood that structural elements of other shapesthan those illustrated in the FIGS. 1.3, 3.3, 4.3, 5 to 7, and 8.3 willrequire caissons/casings 1 of other corresponding or matching shapes.

As illustrated in FIGS. 1.1 to 8.4, there is a gap 2.1 between the bodyof the inner drilling assembly 3 and the interior surface of the caissonor casing 1. The body of the inner drilling assembly 3 can furthergenerally conform to the shape of the interior of the caisson 1. Thisgap is usually of the order of 5 to 10 millimeters, but variations fromthis range are possible. When the embodiment is used in a wateryenvironment such as the ocean, harbour, or river, water is allowed toingress into the interior of the caisson/casing 1 through the gap 2.1.Water ingress into the caisson or casing 1 is also possible through anyother apertures or holes provided on the wall of the caisson or casing1. Thus in circumstances where the embodiment is used in a wateryenvironment, water is allow to enter and may fill the caisson/casing 1.The water ingress helps the caisson/casing to sink into the friableground.

Illustrated in FIG. 9 is a caisson/casing 1 and an inner drillingassembly 3 with three expanding drill bits 4 driven by hydraulic motors5. The motors 5 are kept in approximate synchronization by the hydraulicflow divider 7. The flow divider 7 can be located within the innerdrilling assembly 3 or as shown in FIG. 9 where it is external to thecaisson/casing 1. The motors 5 have drive shafts 6 that pass throughbearings 8 to the bits 4.

Flushing hoses 14 supply air or liquid to the bits 4 through the bearing8 and the shaft 6 to a location past the base 9 of the bearing 8, andout through the flushing hole 15. Hydraulic hoses 13 connect the divider7 with the motors 5. A latch assembly 10 on the drilling assembly 3locates the inner drilling assembly 3 with the caisson/case 1, andengages apertures 11 in the caisson or casing 1. A lifting assembly 12is provided to remove the inner drilling assembly 3 from thecaisson/casing 1 when the bits 4 are retracted. The lifting assembly 12is connected to the latch assembly 10 so that when tension is applied tothe lifting assembly the latch 10 will automatically detach from thecaisson 1. This attachment is not shown on the drawings.

In operation, the periphery of the body of the drilling assembly 3conforms as close as practical to the internal rim of the leading edgeof the caisson 1, which will preferably, on its inside, be of a constantcross section. This relationship of conformity precludes or reduces theentry of material into the caisson 1. The drill bits 4, by theirrotation, will worry, plasticize, fluidize, or disturb the ground. Thedisturbance can be also helped or enhanced by the injection of fluidsthrough the flushing hole 15. The ground, so disturbed, is forced by thecombined mass of the caisson 1 and the drilling assembly 3 to moveoutward from underneath the drilling assembly 3 and upward as theassembly sinks.

Illustrated in FIG. 10 are examples of two drill bits which areavailable and can be used with the embodiments described above. Othertypes of expanding drill bits, some called under the name ‘reamers” or“under reamers” which may or may not require rotation to cause expansionor counter-rotation to cause contraction, are also known which can alsobe used with the embodiments of the present invention as describedabove.

In respect of the above embodiments, when the caisson or casing 1 hasreached the required depth, the rotation of the expanding drill bits 4,4.1, 4.2, 4.3 are reversed in the direction 16 of FIG. 10, retractingthe cutting edges. The inner drilling assembly 3 can then be detachedfrom the caisson/casing 1 and then removed from the caisson/casing 1.Once the required depth of caisson/casing 1 is reached, a structuralelement, such as a poured concrete element (such as a wall, a block,retainer), or a preformed concrete shape, can then be formed or placedinside the caisson/casing 1 and then caisson/casing 1 removed leavingthe structural element in position, and allowing the caisson/casing 1 tobe re-used.

The structural elements placed inside the caisson/casing 1 can be madefrom concrete, steel or any other material, and may include reinforcingmade from fibre glass or non-corroding reinforcing material.

The structural element can be provided with a drain hole, or drainageholes.

The drainage holes in the structural element can be provided with astrip drain. The strip drain can be protected by geo fabric.

The structural element can be provided with a lifting eye, or liftingeyes so it can be lifted and deposited into position in thecaisson/casing 1.

The structural element can be provided with a grout tube, or tubes toallow grout, or other medium, to be pumped to the base. The grouting canbe done before during or after the withdrawal of the caisson/casing 1.

The structural element can be provided with a void or a multiple ofvoids to allow a jet grouted pile, or piles to be constructed below theelement.

The structural element can be provided with a void, or voids to allowthe installation of a grouted rock dowel, or dowels below the element.The structural element can also be provided with reinforcement bars toallow attachment of a capping beam. The structural element can also beprovided with cast in place penetrations, i.e. through apertures, toallow the reinforcement bars to be grouted in place after casting.

After the structural element is placed in the caisson/casing 1, a freeflowing material either granular or liquid can be placed in the caissonas it is withdrawn to fill the void left by the caisson/casing 1. Thecaisson or casing could alternatively be left in situ, as a finalstructural element. Furthermore, the caisson or casing could also beused as formwork, to e.g. form or cast in place a concrete structuralelement.

In respect of the description of what is positioned inside thecaisson/casing 1, after it has achieved a desired depth, as describedabove in paragraphs [0072] to [0080] has not been described in anydetail, nor illustrated, as these aspects are not part of the inventiondescribed in this specification, and further will be commonly and widelyknown by a person skilled in this art.

Illustrated in FIG. 11 is a manual release system to separate thedrilling assembly 3 from the caisson/casing 1. In this manual releasesystem the lifting cable 12 connects to a lifting flange 12.1. The leftside of FIG. 11 shows the system when the drilling assembly 3 is lockedby latches 10 to latch holes 11 thus locking the two together. Thelifting flange 12.1 has a lifting bolt 12.3 which passes through anupper frame member or component of the drilling assembly 3, and issecured in place with an intervening compression spring 12.2, washer12.4 and nut 12.5. The lifting flange 12.1 has a pivot connection 10.3to pivotally connect the latch body 10.1, and the latch body 10.1 ispivotally connected by pivot 10.2 to the mounting plate 10.4 which issecured to the drilling assembly 3. Thus, according to the right handside of FIG. 11, when the lift assembly 12 applies sufficient force tothe lifting flange 12.1, so as to overcome the spring force of thespring 12.2, this will move the bolt 12.3 upward relative to thedrilling assembly 3, which causes a rotation of the latch body 10.1around relatively stationary pivot 10.2, thus withdrawing the latch 10,out of latch hole 11, thus allowing the drilling assembly 3 being ableto be withdrawn from and relative to the caisson/casing 1.

Illustrated in FIG. 12 is a caisson/casing 1 and drilling assembly 3,which is similar to that of FIG. 9, and like parts have been likenumbered. The difference is that the drilling assembly 3 is able to bemoved downward relative to the caisson/casing 1, by means of spacedhydraulic or pneumatic cylinders 100, which push or pull against thelifting frame 12, which is held in place by the latches 10 in latchholes 11 in the caisson/casing 1. The same pushing and pulling forcecould be provided by a similar apparatus external to the caisson orcasing 1. At a desired depth, the cylinders 100 are energized to extendso as to push (or pull) the drilling assembly 3 downward. By retractingthe cylinders 100, the caisson/casing 1 can be pulled downward into thedrilled hole. Then the drills active again, pushed downward by theextending cylinders 100 etc.

It will be noted from FIGS. 1 to 11 that the body of the drillingassembly 3 is of a shape and size which effectively, or substantially,closes off the opening formed by the inner periphery of the caisson orcasing 1. This is the case whether the caisson or casing 1 is of arectangular or curved shape, or whether of a more complex shape such asan arc or T-shape.

It is to be noted, from the embodiments depicted, that there are two ormore drilling heads used to create an area that generally overlaps withthe opening or footprint of a caisson or casing having a single opening.

FIGS. 13.1 to 13.3 depict a method of grouting the vertical spacesbetween inserted precast panels. FIG. 13.1 shows a casing or caisson 1which is advancing downwardly, aided by the action of the drill bits 4.As discussed previously, once the drilling bits 4 and caisson/casing 1advance to the required depth, the drill bits 4 are retracted andremoved. The caisson or casing 1 supports any pre-existing sea-wallsnearby or adjacent, while a preformed structural panel 17 is insertedinto the caisson/casing 1, before the caisson/casing 1 is removed. Whenthis process is repeated and a further panel is inserted adjacent thefirst panel, a gap in the form of a vertical space 17.1 will be leftbetween the panels 17.

To seal or close the gaps 17.1, the panels 17 will be grouted. To dothis, a stocking 18 is placed over a grout line 19 to be inserted in agap 17.1 between the panels 17. The stocking 18 can be chosen frommaterials such as canvas, plastic, any appropriate nylon, orgeo-textile. The grout line 19 is then pushed to the bottom of the gap17.1. As the grout material is being pumped into the gap 17.1, the groutline 19 is withdrawn. As shown in FIG. 13.2, the panels 17, on theirvertical side edges, have grooves or formations. As the grout is pumped,the material conforms to the space formed by the grooves or formationsbetween adjacent panels 17, and forms a key 20 between adjacent panels17.

FIGS. 14.1 to 14.3 depict a method of grouting the toes or lowerportions of the structural panels 17. The drilling assembly 3 and thecaisson/casing 1 are larger than the panels 17. Therefore, after thecaisson/casing 1 is withdrawn, the panel 17 is encapsulated by thedisturbed ground. Grouting the toes or lower portions of the panels 17in the ground will enhance the stability of the panels 17. A grout tube21 is precast in each panel 17. The grout tube 21 runs the whole lengthof height of the panel 17. Grout 22 is pumped into the grout tube 21.The grout 22 used for toe grouting generally has a specific gravity ofapproximately 2, which is higher than the specific gravity of thedisturbed, plasticised, worried, or fluidized portion of the friableground. As the grout 22 is denser than the disturbed, plasticised,worried, or fluidized ground, the pumped grout will displace thedisturbed ground to encapsulate the corresponding panel 17. The grout 22is pumped after the casing is taken out to at least the desired groutheight. The volume of the grout 22 to be pumped will therefore bedetermined by the difference between the desired grout height multipliedby the difference between the cross sectional area of the resulting holeand the cross sectional area of the panel. Once this is done, thegrouting procedure of FIGS. 13.1 to 13.3 can be employed to key in orlock adjacent panels together.

As shown in FIGS. 15.1 to 15.3, in some situations, one or more of thepanels will be placed over rocks or hard-ground 24 which is not friableor not friable enough. The caisson/casing 1 will not sink into the hardground 24. A panel 17 suitable for placement over hard ground 24 canhave cast into it a penetration 23, i.e. a through aperture. Thepenetration 23 is usually centrally located with respect to the panel17. The rock cutting drill bit 4 is then operated to drill a hole 25into the hard ground 24 through the penetration 23, so that a hole 25 isdrilled to coincide with the penetration 23. A reinforcement dowel 26can be placed into the hole 25, and grouted in place through the groutline 27 which extends to the bottom of the hole 25.

Any reinforcements are preferably of a non-corrodible type material,such as glass fibre, reinforcing carbon fibre rods or stainless steel,etc.

FIGS. 16.1 to 16.6 depict securing or casting a capping beam 28 to thetops of the structural panels 17. As shown in FIG. 16.1 to FIG. 16.3,the structural panels 17 can have blind apertures or penetrations 29accessible from the tops of the panels 17 Separate reinforcement bars 30adapted to be partially received by the blind apertures 29 are groutedinto place in the apertures 29. Alternatively, the panels 17 can havereinforcement bars 31 cast into them. A capping beam 28 which has beenpre-cast is then attached to the dowels 30, or alternatively the cappingbeam is cast onto the dowels 30. The capping beam 28 will have holeswhich correspond to the reinforcement bars 30, 31. The reinforcementbars 30, 31 are fitted into the corresponding holes in the capping beam28 as the capping beam 28 is attached. FIG. 16.4 depicts the reversescenario, where inserted dowels 30 or precast dowels 31 are provided ina pre-cast capping beam 28. The capping beam 28 is then attached to thepanels 17 which have the required apertures to accept the dowels 30, 31.

More preferably, as shown in FIG. 16.5, the capping beam 28 can castdirectly into a formwork provided around the tops of the panels 17, inwhich case the capping beam 28 will be cast around the dowels 30, 31 andthe panels 17. As shown in FIG. 16.6, it is alternatively possible tocast a capping beam 28 onto the panels 17 or attach a precast beam 28 tothe panels 17, and then drill securing bolts to secure the beam 28 andpanels 17 together.

FIGS. 17.1 and 17.2 depict concrete caissons or casings 1 that areformed with reinforcements 1.3 and that are left in situ rather thanremoved, after the drilling assembly 3 has been retracted. The caissonsare left as structural elements. The caisson/casing 1 may or may nothave a structural core. It can be left in situ as a structural elementitself, or it may have a cast in place concrete structural core 1.2 thatis formed inside the caisson 1.

Referring to FIGS. 18.1 to 18.2, the panels 17 or capping beams 28further include anchoring ties 32 to stable land which is adjacent thepanels 17. In FIG. 18.1, holes are drilled into the adjacent stable landto insert the ends of the ties that are distal from the panels 17. Theproximal ends of the ties are bolted or otherwise secured to the cappingbeams 28 or panels 17. The anchoring ties 32 helps secure the panels 17against the weight of the friable land pushing directly or indirectlyagainst the panels 17. In FIG. 18.2, the panels 17 are installed next towall members 17.2 which are pre-existing and deteriorating, with thepanels 17 being put in place to shore up or take over from the oldpre-existing retaining panels 17.2. In this case, an old anchor 32.2 isalready in place and tied to adjacent land. An extension 32.1 is linkedto the old anchor 32.2 to extend the tie 32 to the capping beam 28 forthe new panel 17. The extension 32.1 can be precast into the beam 28, orthe capping beam 28 for the new panel 17 is post tensioned to theexisting capping beam 28.2.

FIGS. 19.1 to 19.4 depict the movement of the bed dirt, mud, or othermatter which is displaced by the drilling assembly 3. As discussedbefore, as the drilling assembly 3 drills into the friable ground, theweight of the caisson/casing 1 enables the caisson 1 to sink down to thedrilled level. As mentioned above, the caisson 1 is also able to sinkbecause the cuttings tend to be displaced upwards. Together the actionsand weight of the drilling assembly 3 and caisson 1 progressively causeportions of the friable ground to become plasticised, which allows theaction of gravity to sink the caisson to a desired depth.

The assembly 3 and caisson 1 displace the disturbed or drilled matter33, which tends to accumulate upwards as shown in the arrows included inFIGS. 19.2 and 19.3. The arrows of FIG. 19.3 depict the process whereby,as the caisson and drilling assembly advance deeper into the hole, moredisturbed or drilled matter 33 is accumulated upwardly. The previouslydisplaced cuttings or matter is pushed upwards by newly displacedmatter. Once the drill assembly is retracted, and a structural elementsuch as a panel 17 is inserted into the caisson 1, the caisson can beremoved. Upon the removal of the caisson 1, the previously pileddisplaced matter 33 (if toe grouting is not done) now flows downwardly,in the direction indicated by the arrows in FIG. 19.4, to fill the spacevacated by the caisson 1. Due to the friable nature of the environment,the drillings and cuttings are plasticized. Therefore, there is norequirement to actively pump the bed matter out of the drilled hole toprevent blockage.

Referring to FIGS. 20.1 to 20.8, in some circumstances, the depth of thehole to be drilled will be greater than the length or height of acaisson 1 that can be used with the drilling equipment. In thissituation, additional caissons 1′ can be added to follow the initial orleading caisson 1 which has been inserted or partially inserted into thehole, in an end-to-end fashion. Here, the attachment of the caissons 1,1′ is done whilst the trailing edge of the first inserted caisson 1 isstill accessible. Preferably, the neighbouring caissons 1, 1′ will beattached together. This way, the plurality of caissons 1, 1′ is able tobe removed in a single operation. The skilled person will appreciatethat more caissons can be added for insertion into holes of greaterdepths as needed.

FIG. 21 is a schematic view of one manner of attachment betweenneighbouring caissons. As shown, the lower or leading caisson 1 has arim, flange, bead, or generally a projection 34 around its trailingedge. The adjacent, subsequently inserted caisson 1′ which trails theother caisson 1 includes a cooperating projection 35 at its leadingedge. The cooperating projection 35 includes a groove 36 which isadapted to receive the trailing projection 34 of the previous caisson 1.The upper or subsequent caisson 1′ is further constructed from twohalves 1′-1, 1′-2, respectively having the grooves 36-1, 36-2. The twohalves 1′-1, 1′-2 are two vertical halves of the subsequent caisson 1′.The halves 1′-1, 1′-2 have a vertical parting plane S and are initiallyspaced apart from each other. The vertical halves 1′-1, 1′-2 are movedtoward the trailing edge of the first or previously inserted caisson 1,then closed toward each other and onto the previously inserted caisson1, so that the grooves 36-1, 36-2 together are fitted onto theprojection 34, attaching the caissons 1, 1′ together. The two verticalhaves 1′-1, 1′-2 of the subsequent caissons 1′ can further be securedtogether by e.g. bolts. The skilled person will appreciate that althoughthe subsequent caissons or casings 1′ are described as having two halfsections, they can each be constructed of three or more verticalsections, and then assembled in the manner described above.

When the caissons 1, 1′ need to be removed, the upper most caisson 1′ ishooked or otherwise attached to a lifting device, and then both caissons1, 1′ will be lifted together because of the attachment between thecaissons 1, 1′.

The caissons 1, 1′ can have identical features—that is each caisson 1has a leading projection 35 and a trailing projection 34 as describedabove, and is constructed from two vertical halves. This constructionallows the subsequent caisson 1′ to be added unhindered by the supportor cables for the drilling assembly. Alternatively, the skilled personwill appreciate that the first inserted caisson does not need to have aleading edge projection 35 or be constructed from multiple sections.

While the preceding passages describe prior art systems, these systemsare particularly useful together with the following inventive aspectsand embodiments, as described below with respect to FIGS. 23 to 50.

In broad terms, the embodiments illustrated in FIG. 24, FIG. 28, FIGS.32 to 34 and FIGS. 51 to 62, all provide a caisson or casing 107 forinstalling a sheet 102 into a ground or underwater location, the caisson107 having a shaped wall 107.1 which is open for a predetermined length,which is adapted to receive and connect to an excavation means 3 withinthe confines of the caisson or casing 107.

The shape of the shaped wall 107.1 will be dependent upon the sheet pileor other retaining wall element that needs to be positioned in ground orunder water location. The shaped wall can be made from any number ofwall segments needed to match the shape of the sheet pile beinginstalled. So, for the shaped wall 107.1 of FIG. 24, there are segments107.2 to 107.10, while shaped wall 107.1 of FIGS. 32 to 34 have segments107.2 to 107.8, and the shaped wall 17.1 in FIG. 38, is made from threesegments 107.2 to 107.4. In the case of the FIGS. 24 and 32 to 34 shapedwalls, these almost entirely match the shape of the sheet pile 102 beinginstalled.

The shaped wall 107.1 has its free sides A and B each having a clutch,and a connecting section 125 or 111, in the case of the systems of FIGS.24, 30, 38, 50A and 69 is provided which closes the caisson 107 and orthe shaped wall 107.1.

The connection section 125 or 111 (as seen in FIG. 30) can have a firstwall portion 125.1 with a mating clutch 125.2 and 125.4 to join with theclutches at the free sides A and B of the shaped wall 107.1.

The connection section 125 of FIGS. 24 and 38 also include a second wallportion 125.10 which is at an angle to the first portion and whichterminates in at least one element mating join formation or clutch, inthis case a third clutch 125.11 which is adapted to engage the freeclutch at a side of a sheet 101 previously inserted in the ground orunderwater location.

The connection section 125, as in the case of FIG. 38, is a sheet pile,which is adapted, in use, to be separable from the shaped wall 107.1.

The connection section 125, in the case of FIG. 38 has a first clutch125.2 and a second clutch 125.4, the first clutch 125.2 located at aside of the connection section 125 and the second clutch 125.4 locatedintermediate the free sides 125.10 and 125.1 of the connection section125, so that the first and second clutches 125.2 and 125.4 are adaptedto connect to the two clutches at the free sides A and B of the shapedwall 107.1.

The connection section 125 has the element mating join formation orclutch 125.11 located at the other side of the connection section 125from the first clutch 125.2, with the element mating join formation orclutch 125.11 being adapted to engage a free clutch being at a side of asheet 101 previously inserted in the ground or underwater location.

The element mating join formation or mating clutch 125.11 on theconnection section 125, by being adapted to engage a free clutch on asheet 101 previously inserted in the ground or underwater location, isadapted to act as a guide to guide the caisson or casing 107, and anexcavation means 3 combined therewith, as excavation or drilling occurs.

The element mating join formation or clutch 125.11 is adapted to belocated outside an excavation footprint 108 of an excavation means whichis at the end of the caisson or casing 107, but remains within theexcavation footprint 105 of the ground disturbed when placing sheet 101.

The caisson or casing 107, as best illustrated in FIGS. 24A, 30A and 39have a releasable locking mechanism 300 which allows releasableinterconnection between the connection section 125 and the shaped wall107.1.

The locking mechanism 300 can include any lock mechanism, such as a pinmeans like shear pin 126, which sits in aligned apertures passingthrough mating clutches on the shaped wall 107.1 and the connectionsection 125, in which case it will be a clutch locking mechanism, whichcan be removed when needed. The apertures can be of any appropriateshape, and the pin can simply match that shape. However this is notpreferred due to the importance of the clutch allowing relative slidingmotion. Alternatively, and more preferred, as illustrated in FIGS. 24A,30A and 39 one of the connection section 125 or the shaped wall 107.1can be provided with a flange portion 125.13 provided to receive theremovable pin 126. The locking mechanism 300 is preferably at the topand/or bottom of both ends of the shaped wall 107.1 so that when it isupended, a lock between the clutch on the shaped wall 107.1 and thesheet 102/103 can be effected.

The caisson or casing 107 when combined with an excavation means 3 canbe adapted to allow the excavation means 3 to provide an excavationfootprint 108 which can overlap an excavation footprint 105 related tothe sheet 101 previously inserted in the ground or underwater location.

After the caisson or casing 107 has been positioned in the ground orunderwater location, the connection section 125 is separable from theshaped wall 107.1, by the mechanisms described above.

The shaped wall 107.1 is adapted so that a sheet 102 can be made toengage the clutch of a previous sheet 101, and pushed or hammered orvibrated into position.

The shaped wall 107.1 is removeable from the ground or the underwaterlocation, after the sheet 102 is positioned.

The drilling assembly as described in relation to FIGS. 1 to 22 can becombined with the caisson or casing 107 of FIGS. 23 to 50.

The excavation means 3 substantially closes off an opening formed by aninner periphery of the caisson or casing 107, even though in theembodiment of FIGS. 32 to 34, there is an open side to the caisson orcasing 107.

As best illustrated in FIGS. 24 and 38 there are multiple excavationmeans 109 used for the caisson or casing opening.

The excavation means 109 excavates hard ground or drills hard ground,allowing the caisson or casing 107 to be positioned to a predeterminedor required depth.

As the connection section 125 has to be separated from the shaped wall107.1, there needs to be provided means, such as releasable lock means10 described above, which can disconnect them. The connection section125 preferably does not connect to the excavation means 3 or releasablyconnected to the excavation means 3 or.

It may be preferred that the excavation means 109 to be associated withthe caisson or casing 107, be connected to or supported only by theshaped wall 107.1.

When installing the “first” sheet pile 101.1, as best illustrated inFIG. 30, then either the a first caisson 107 shaped and sizedspecifically to accept the first sheet 101.1 can be utilized. In a firstexample the sheet 101.1 will be a standard width sheet pile, and thecaisson 107 of FIG. 30 having increased dimensions when compared to thatof FIG. 24 which is being used to install a subsequent sheet pile.Alternatively the same caisson 107 from FIG. 24 can be used, but a firstsheet 101.1 can provided which has a reduced width, so that the sheetpile 101.1 fits within the caisson 107 and connection piece 111.

As is described above in respect of FIGS. 1 to 22, the embodiments ofFIGS. 23 to 50 are constructed so as to attach an excavation tool 3within the lower end of the caisson 107. The tool 3 is shaped to fitinside the caisson 107 being used. The tool 3 consists of two or moredrill bits (which may not be expandable) or two or more expandable drillbits 109 arranged so as in their expanded state they excavate beyond theboundary of the caisson or casing 107.

The drill bits 109 are provided with a means of flushing the hole with afluid. The fluid may be, water, polymer, mud or any other suitablefluid. When rotated in the expanded state the drill bits will allow thecaisson 107 to advance to the required depth, through hard ground,without noise or vibration.

When the required depth is reached the expandable drill bits arereturned to their retracted state. In this state they are containedentirely within the caisson 107. The tool 3 can then be detached andremoved from the caisson 107.

When the tool 3 has been removed, in the manners described above withrespect to FIG. 1 to 22, the first sheet 101 or 101.1 can be placed tothe correct depth inside the caisson 107.

When the first sheet 101 being full sized positioned by the caisson 107or first sheet 101.1 being of reduced size positioned by the firstcaisson 107, is in place, then caisson 107, or the first caisson 107,can be removed and a second caisson assembly 107 will now be required,due to the change in shape of the sheet pile 102. The second caisson 107is shaped so as to accept the second sheet 102. The second caisson 107is also shaped to fit the tool 3. The second caisson 107 can be in twoparts, a connecting section 125 and a main body or shaped wall 107.1.The connecting section 125 can be attached to the first sheet 101 or101.1 by the clutch and to the body by two clutches 125.2 and 125.4 orby other convenient means.

In the systems of FIGS. 23 to 37, the connecting section 125 of thecaisson 107 attached to the first sheet 101 is removed leaving the bodyor shaped wall 107.1 of the caisson 107 in place.

With the connecting section 125 and the tool 3 removed, then a secondsheet 102 can be attached to the first sheet 101 and placed to thecorrect depth. With the second sheet 102 in place the shaped wall 107.1of the caisson 107 can be removed.

If in the installation of the piles a smaller first pile 101.1 is usedthen the first caisson can now be re-used to install a third pile. Or ifa first caisson and second caisson have already been used, then a thirdcaisson assembly 107 will now be required. It will be similar to thesecond caisson 107 but a mirror image. This caisson 107 is shaped to fitthe third sheet 103.

The third caisson, as described above is advanced, without noise orvibration, and the tool 3 removed.

The third sheet 103 can be attached to the second sheet 102 and placedto depth. The third caisson 107 can then be removed.

By repetition of the steps described above a sheet pile wall can beconstructed in hard ground without noise or vibration.

Those skilled in the art will understand that utilizing several caissons107 and possibly multiple drilling tools 3 will slow down theinstallation process. Whereas it can be speeded up if the process used asingle tool and a single caisson assembly. The connecting section 125 ofthe second caisson could be replaced by a blank part so that theassembly took the shape of the first caisson, or something similar.

Alternatively, the shaped wall 107.1 can be constructed so that thesecond caisson assembly 107 could be turned upside down, therebyallowing it to take the shape needed for the of the third caissonassembly. Likewise if the tool 3 is constructed symmetrically about itsminor axis it will fit both a right hand and a left hand caisson.

Those skilled in the art will understand that sheets can be fabricatedwith the clutch misaligned. This will allow the next sheet to be placedat an angle to the XX axis. By this method sheet pile walls, other thanstraight can be constructed.

After the sheet piles 101, 102, 103 etc. have been placed in position,the base of the sheets 101, 102, 103 etc. can be grouted into the holethat has been drilled. A polymer or bentonite drill fluid will greatlyassist this process. This grouting should take place some distancebehind the advancing pile wall under construction and should not beallowed to impinge on the drilling of the caisson for the next sheet.

While the following description is in respect of one section of sheetpile it will be readily understood that the present invention can beapplied to other sections.

While the following description is in respect of placing one sheet at atime it will be readily understood that the present invention can beapplied to install multiple sheets at one time.

FIG. 23 shows three sheets 101, 102 and 103 connected by clutches 104.The sheet pile 101, 102 and 103 in this instance is Larsson type 755sheet pile. For the purpose of this description the sheets 101, 102 and103 are to be installed in numerical order. The longitudinal axis XX isshown for reference

FIG. 24 shows the first sheet 101 in place. The boundary of the grounddisturbed or drilled during the installation of the first sheet 101 isshown by the intermittent line 105. The connecting section 125 of thecaisson 107 attaches to the first sheet 101 by clutch 125.11 whichconnects to the clutch 104 on the first sheet 101. The other end ofconnection piece 125 connects to the body or shaped wall 107.1 of thecaisson 107 by two clutches 125.2 and 125.4 to the clutches at the endsA and B.

In FIG. 24, a drilling tool 3 is shown attached inside the caisson 107.The attachment of the tool 3 to the caisson 107 is not shown, but is asdescribed above in relation to FIGS. 1 to 22. Four drills 109 withexpandable drill bits are located within the tool 3. The boundary 108 isthe limit of the ground disturbed by the drill bits 109 in theirexpanded state. It should be noted that the connection section 125 hasits clutch 125.11 beyond the boundary of the disturbed ground 108 but itis inside the boundary of the previously disturbed ground 105. It shouldalso be noted that the boundary 108, that is, the limit of the expandedbits, passes close to, but does not interfere with the first sheet 101.The tool 3 is symmetrical about the minor axis YY. The inner void of thecaisson 107 is shaped to match the symmetry about the axis YY, but isnot actually symmetrical. This relationship and arrangement allows thecaisson 107 and the tool 3 to be used when the caisson 107 is in amirror reverse configuration. This will be necessary to place sheet 103.

For the purpose of the following description the caisson 107 will beviewed along the YY axis from the point it coincides with the XX axis.FIG. 24 is thus described as a caisson 107 with a right handinterconnection. A caisson 107 with a left hand connection will berequired to place sheet 103. The caisson 107 with the tool 3 attachedand the expanding bits 109 in their expanded state, extending to theboundary 108, can now be drilled to the required depth.

FIG. 25 shows the caisson 107 after it has been drilled to the requireddepth and the interconnecting section 125 removed. The tool 3 has beencollapsed so that it is now contained within the caisson 107. In thisstate the tool 3 can be detached and removed from the caisson 107.

FIG. 26 shows the caisson 107 with both the interconnecting section 125and the tool 3 removed. The caisson 107 can now accept sheet 102.

FIG. 27 shows the second sheet 102 connected to the first sheet 101inside the empty caisson 101. The sheet 102 can then be pushed to thecorrect depth. The caisson 107 can then be removed.

FIG. 28 shows the second sheet 102 connected to the first sheet 101 andthe caisson 107 removed.

FIG. 29 is similar to FIG. 24 but the assembly is now a caisson 107 witha left hand interconnection shaped to accept sheet 103. The change inhandedness can be provided either by turning both the caisson 107 andthe connection piece 125 upside down or it could be a purpose builtcaisson. Note that because the void in the caisson 107 is symmetricalabout the YY axis, the tool being also symmetrical about the YY axiswill fit inside the caisson 107 as before, once it has been rotatedthrough 180 degrees.

The process of drilling the caisson 107 to the correct depth, removingthe connection piece 125, detaching and removing the tool 3, placing thenext sheet 103 and removing the caisson 107 can now be repeated.

FIG. 30 shows the caisson 107 with a blank connection piece 111 in placedrilled to depth and the tool 3 removed. This caisson 107 can bemanufactured in one piece but in this configuration it could be used toplace the first sheet 101. The purpose of the blank connection piece 111is so the caisson 107, in conjunction with the tool 3, can be used toplace sheets 101 and subsequently with connection piece 125 of earlierFigures, used to place the second sheet 102 and third sheet 103. Thefabricated first sheet 101 is shown inside the caisson 107. The caisson107 and the connection 111 can be withdrawn leaving the sheet 101 inplace to the correct depth.

FIG. 31 shows the closure of a sheet pile wall. A fabricated sheet pilepiece 114 is used to connect sheet 112 to the last full sheet 113 bothpositioned in the ground. The fabricated connecting piece 114 is able tobe placed because the disturbed ground shown by the intermittent lines115 and 116 overlap. To arrive at this position sheet 113 may have to befabricated with a reduced width as sheet 101 or 101.1 in FIG. 30.

FIG. 32 is similar to FIG. 27 except it shows a caisson 107 shaped toaccept a different sheet pile section, in this instance Larsson type ZK675 sheet pile. The caisson 107 is shown with the connecting piece 125removed. The sheet 102 is shown connected to the previously placed sheet101.

FIG. 33 shows a caisson 107 shaped to accept Larsson type ZK 675 sheetpile. This caisson 101 is open sided, with no connecting piece beingused. In certain types of ground this may be possible.

FIG. 34 shows a caisson 107 shaped to accept Larsson ZK 755 sheet pile.This caisson 107 is open sided, in that between the ends A and B it isopen, but are shaped to be directed inwardly to the sheet pile 101, tomore closely fit to the previously placed sheet 101. If desired, thesheet pile 101 can have welded or attached locating blocks or locatingflanges 101.2 and 101.3, so as to provide a guide for the inward ends Aand B to travel between. In certain types of ground this may bepossible, and is expected to work effectively, when the sheet pile isinstalled shortly after the drilling has been completed.

As can be seen from the above description, in broad terms there isdescribed a method of inserting a sheet or sheet pile 102, 103, themethod including: providing a caisson or casing 107 as described above;providing an excavation means 3 which is expandable to excavate andretractable to within the confines of the caisson or casing 107;utilizing an earlier installed sheet pile 101, 101.1 a drilling guide orif the caisson or casing is open, overlapping the excavation area of thenew sheet pile 102 with that of the earlier installed sheet pile 101;installing a sheet pile 102 or 103 by means of the caisson or casing.

The method described above includes the use of a connection section 125or 111 to close the caisson or casing or shaped wall 107.1.

The connection section 125 enables the caisson or casing 107 to beguided by the earlier installed sheet pile 101. As illustrated in FIG.50A it can be seen that the connection section 125 could also beconstructed from a V-shaped type of construction where the free legsinclude the clutches 125.2 and 125.4, and the vertex of the V has theclutch 125.11 extending from it.

The connection section 125 as in the case of the embodiment of FIG. 38also acts as a sheet pile 102 and remains in the ground or underwaterlocation.

FIG. 35 shows previously placed sheet 101 which has penetrated a hardlayer of ground 117. The caisson 107 attached to sheet 101 has drilledthrough the hard ground 117 and with the tool 3 (not shown) removed, andcan now accept the next sheet 102 (not shown on the drawing). Onceplaced through the hard ground inside the caisson 107, the sheet 102 canbe placed to depth by conventional means- that is, this apparatus issuch that it does not require the caisson 107 to move down further.Ground level 118 is shown.

FIG. 36 shows a caisson 107 which has drilled through a layer of softground 121 and then into a hard sea bed 119. Water level 120 is shown.

FIG. 37 shows the sheet pile 102 which has been place through thecaisson 107. After the caisson 107 has been removed grout 122 can bepumped to the bottom of the drilled hole in the seabed 119. The sheet102 is now grouted into the drilled hole in the seabed 119. The pile 102is now able to support the ground 121. Up to ground level 118. Waterlevel 120 is shown.

Illustrated in FIG. 38 is another sheet pile installation system andmethod.

The caisson 107 is effectively constructed in two halves. The first halfbeing a shaped wall 107.1 to accept the drilling tool 3. The second halfbeing a connection section 125, which will also be the sheet 102 to beinstalled. A clutch 125.4, or other means of attachment, must be adheredor riveted in the case of some sheet pile material, or welded if steelor aluminium, or by sheet bolts in the case of GFRP, to one side of theconnection piece 125 or sheet to be installed. The first half 107.1 ofthe caisson 107 will attach to the second half 125 by this clutch andthe existing clutch on the other side. The two halves now forming onecaisson can be attached to the clutch 104 of the previously placedadjacent sheet 101, by means of the clutch 125.11 located on the end ofthe sheet pile 125/102. As before the drilling tool 3 is shaped to fitinside this caisson 107.

FIG. 38 shows a section of clutch 125.4 welded to one side of the sheetto be placed 102. This clutch 125.4 can be continuous or it can beintermittently present and engaging depending upon the application. Thesheet to be placed 102 is attached to the previously placed adjacentsheet 101. The shaped wall 107.1 or caisson half is attached to thesheet 102 to be placed by both the welded clutch section 125.4 and theexisting clutch on the other side. The two halves now form one caisson.Inside this caisson 107 is the drilling tool 3 with four expandabledrills 109, with the drilling tool 3 being attached to the lower end ofthe caisson 107. When the drilling tool 3 is in the expanded state theboundary of the ground disturbed 108 is beyond the caisson 107. Thecaisson 107 can now be drilled to depth. When the caisson 107 has beendrilled to the correct depth the expandable drill bits 109 can becollapsed. When the bits 109 have been collapsed both the drilling tool3 and the caisson half or shaped wall 107.1 can be withdrawn separatelyor in unison. The result being that the sheet 102 has been positioned inthe required place.

The caisson half or shaped wall 107.1 is then upended and combined orattached to the next sheet 103 not shown on the drawing. As the drillingtool 3 is symmetrical about the YY axis, after it is rotated through 180degrees, it can again be attached to the lower end of the caisson andthe drilling process repeated.

As described earlier, the excavation means 3 is detachably attached tothe caisson 107 or the shaped wall 107.1, and is preferably a drillingtool 3 comprised of two or more drill bits 109, such as expandable drillbits. In the expanded state the drilling tool 3 excavates beyond all, orsubstantially all, of the boundary of the lower end of the caisson 107.In the collapsed state the drilling tool 3 is contained wholly withinthe foot print of the hole or aperture through the lower end of thecaisson 107. The excavation means 3 is positioned so as to close offall, or substantially all, of the lower end of the caisson 107. Theexcavation means 3 being detachably connected to the caisson 107 ensuresthat when attached to the caisson 107, the caisson 107 will advance asthe tool 3 drills. When the drilling tool 3 is detached it can beremoved from the caisson 107. The excavation means 3 will generally beprovided with or connected to a source of flushing air, water, polymer,mud or a combination of any 2 or more of these.

Illustrated in FIGS. 41 to 50 is an excavation means 3 for use with acaisson or casing 1 so as to drill in front of the leading edge of thecaisson or casing 1, particularly in hard ground. The excavation meanshas a body to mount at least two excavation tools 133 so that the twoexcavation tools 133 are distanced or spaced from each other so that theoutside diameter 134 of excavation of the tools 133 are spaced from eachother so that when the body 3 is rotated through 180 degrees, a seriesof overlapping excavations will result. The excavation means includes adetachable connection, as described above, to a caisson or casing withwhich it will be used. The advantage of the excavation means 3 is theability to drill a shaped hole with less drill bits.

The excavation means 3 is a drilling tool or drilling tool assembly, andcan include expandable drilling bits, and there can be an even or an oddnumber of bits or excavation tools 133, as is illustrated in FIGS. 91and 92, or a single excavation tool 133 as illustrated in FIGS. 95 and96. It will be noted in the case of the excavation or drillingassemblies 3 of FIGS. 41, 42, 91, 92, 95 and 96, that there is locatedone excavation tool 133 close to a side wall of the drilling assembly soas to be close to the side wall of the caisson or casing 1, but there isa larger spacing to the opposite side wall, from the only or lastexcavation tool 133.

In summary, FIGS. 43 to 50 show a method of drilling a caisson or casing1, the method including the steps of: providing a caisson or casing 1;attaching to the caisson or casing an excavation means 3; advancing theexcavation means 3 to excavate ground beneath the excavation means 3;withdrawing the excavation means 3 from the caisson or casing; rotatingthe excavation means through 180 degrees; reattaching the excavationmeans 3 to the caisson or casing 1; advancing the excavation means 3 toexcavate ground beneath the excavation means 3 to produce a series ofoverlapped excavations into which the caisson or casing 1 canpositioned.

The following will describe FIGS. 41 to 50 in more detail.

FIG. 41 illustrates a plan view of an alternative caisson 1 with a mainbody of a drilling assembly 3 located inside. The assembly 3 has twoexpanding drills 133, in their collapsed state, attached. The attachmentof the drills 133 is asymmetrical. It will be noted that the caisson 1,is similar to that of FIGS. 1 and 2 above, except that in FIGS. 1 and 2above show three drills 4, whereas the caisson 1 of FIGS. 41 to 50 hasonly two expandable drills 133 which are spaced apart, so that whenrotated by 180 degrees, a series of four bores 134 and 135, as depictedin FIG. 42, will be drilled.

FIG. 42 shows the same plan view as that of FIG. 41, when the expandingdrills 133 are expanded to their outer diameter 134 in their expandedstate. The broken circles 135 illustrate the holes to be drilled next,once the drill tool 3 has been removed from the caisson, then rotatedthrough 180 degrees, and drilling begins again.

Illustrated in FIGS. 43 to 50 is a schematic representation of thedrilling process. FIGS. 43 and 44 is a schematic side elevation and aplan view respectively of a caisson 1 containing a drill assembly 3 withthe expanding drills 133 in their collapsed state, which have not yetbeen locked to the caisson 1, and have not yet arrived into the positionfor the drill 3 and caisson to be detachably secured together. In theposition of FIG. 43, the assembly 3 is ready to advance to the drillinglocation.

FIGS. 45 and 46 are similar to FIGS. 43 and 44, and show the drillassembly 3 after it has advanced, and with the drills in the expandedstate. Once Drilling occurs, two holes will be drilled which coincidewith the drilling diameter circles of FIG. 46, and the holes will bespaced apart, whereby only part of the periphery of the caisson 1 willhave a drilled holed underneath its leading edge.

Once the two holes have been drilled, the caisson and drill assembly ofFIGS. 45 and 46 will then have the drill bits collapsed and the drilltool 3 removed from the caisson 1. The drill tool 3 once out of thecaisson is then rotated through 180 deg. When viewed in plan view andplaced back into the caisson 1, ready to be advanced.

FIGS. 47 and 48 shows the caisson and drill assembly 1 and 3 after thedrill tool 3 has been advanced the second time. The drills 3 are thenreturned to their collapsed state and the caisson 1 advanced.

FIGS. 49 and 50 shows the caisson 1 advanced and the drill tool orassembly 3 collapsed ready to repeat the steps of FIGS. 43 to 50, butstarting on the right side of the caisson.

Illustrated in FIGS. 51 to 57 is a sheet pile placement method andapparatus, similar to that described above. In this method the firstsheet pile 101 is in position to a required depth in hard ground 119having also passed through soft bed 121. It is called “first” only forthe sake of ease of description, as it will be seen in FIG. 51 that thefirst sheet pile 101 connects to an even earlier unnumbered sheet pile.It will also be noted in FIG. 51, that the hard ground to the right ofthe base of the sheet pile 101 has been excavated by the earlier usedexcavation tool.

The second sheet pile 102 is connected to sheet pile 101 by theirrespective clutches, and the sheet pile 102 is pushed down through thesoft layer 121 until its base reaches the start of the hard ground layer119, as in FIGS. 51 and 52.

In FIG. 53 a shaped wall 107.1 and drill assembly 3, are assembledtogether with a trailing leg 3.1 which is preferably connected to thedrilling assembly 3, but may be extending from the shaped wall 107.1.The shaped wall 107.1 has clutches 125.2 and 125.4 to engage clutchesprovided on the sheet pile 102 (such as described above in relation toFIG. 38), with the drilling bits 109, which are schematicallyrepresented by a single bit, being operated without expanding, and“drilling” through the soft bed 121, until it reaches the hard ground119.

As seen in FIG. 54, once the hard ground 119 is engaged, the expandingbits continue to drill, until they pass sufficiently the lower end ofthe sheet 102, and then they are reversed and they slowly expandoutwardly as they drill and undercut the leading edge of the sheet 102.The point at which the expanding bits 109 can be reversed and expandedis when an engagement end 3.2 on the trailing leg 3.1, engages the topedge 102.9 because the distance between the end 3.2 and the drill bit109 has been set for the height of the sheet 102.

The end 3.2 also has the advantage that as the drill assembly 3 movesdown the sheet pile 102, all the while being guided by the sheet 101,the sheet 102 follows the drill assembly 3 downward until, drilling isfinished as in FIG. 55. Whereupon the drill assembly and shaped wall107.1 and leg 3.1 and end 3.2 are withdrawn as in FIG. 56, and the sheetpile 202 grouted in place (once a further sheet along the wall has beeninstalled), and then eventually as in FIG. 57 the ground level side 118,can be back filled to complete the wall construction.

This arrangement of FIGS. 51 to 57 has the advantage that the shapedwall 107.1 does not need to be locked to the sheet 102 by means of theclutches that are engaged, making the process quicker. Additionally thecaisson or casing 107 formed by the shaped wall 107.1 and sheet 102, atthe base of the sheet 102, assists to ensure that soft bed 121 does notrush to fill in the excavation foot print. It will be noted that theShaped wall 107.1 is of a height greater than the depth of soft bed 121and the depth of drilling into hard ground, thus keeping out soft bedmaterial while drilling is occurring

Illustrated in FIGS. 58 to 62 is a sheet pile placement method andapparatus, similar to that described above. In this method the firstsheet pile 101 is in position to a required depth in hard ground 119having also passed through soft bed 121. It is called “first” only forthe sake of ease of description, as it will be seen in FIG. 58 that thefirst sheet pile 101 connects to an even earlier unnumbered sheet pile.It will also be noted in FIG. 58, that the hard ground to the right ofthe base of the sheet pile 101 has been excavated by an earlier usedexcavation tool.

In the method of FIGS. 58 to 62, as in FIGS. 58 and 59, a drillingassembly 3 and shaped wall 107.1 are operatively connected to a sheetpile 102, so that the drilling bits 109 when expanded are below theleading edge of the caisson 107 formed at the lower section of the sheet102 by the joining of the shaped wall 107.1 to the sheet pile 102, byone of the means described above The height of the shaped wall isprovided so that it is higher than the depth to be drilled in hardground 119 plus the depth of the soft bed 121.

In FIGS. 58 to 62, the drill bits 109 are schematically represented by asingle drill bit 109. At the top 102.9 of the sheet 102 is aconventional sheet pile installation tool or piling equipment 139, whichwill drive the sheet pile 102 and drill assembly and shaped wall 107.1through the soft bed 121, until hard ground 119 is encountered. Theshaped wall 107.1 and drill assembly are joined together, and theassembly of them is connected to the sheet 102 by a releasable latchmechanism 10 (such as that described above), which is shown I the lockedcondition in FIG. 59.

Thus as the piling equipment 139 pushes the sheet 102 into the soft bed121, so too does the shaped wall and drilling assembly follow. If neededdepending upon the “viscosity” of the soft bed 121, the unexpanded bitsin the drill assembly can be rotated in an unexpanded condition to helpclear the path for the shaped wall 107.1 and the drilling assembly 3.

Once hard rock is reached the bits 109 are rotated so as to expand underthe leading edge of the shaped wall 107.1 and the sheet pile 102, andcontinues to drill until the required depth is reached, as illustratedin FIG. 60. At this point, as illustrated in FIG. 61, the sheet 102 isat its required depth, and the piling equipment 139, by means of liftingassembly 12, and the disengagement of latch 10, lifts the drillingassembly 3 with the drill bits unexpanded and shaped wall 107.1, upalong the sheet 102 and out ready for the next sheet. Then as in FIG.62, grout 122 can be installed in both the soft bed 121 and hard groundlayers 119, and the ground level 118 back filled to the wall soproduced, but usually a few sheet back if back filling is progressing atthe same time as pile placement is occurring.

Illustrated in FIGS. 63 to 74, is a sheet pile installation method andapparatus similar to that of FIGS. 24 and 29, except that the caisson orcasing 107 and its shaped wall 107.1 has a modified shape, and theconnection section 125 too is modified in shape. Additionally thedrilling assembly 3 has some 5 drills to insert a sheet pile 102.

Illustrated in FIG. 63, the caisson 107 of FIG. 69 is combined by alatch 10 to the drilling assembly 3, preferably before insertion intothe water 120. The caisson 107 and drill assembly 3 are then sunk to thehard ground layer 119 through soft bed 121. This can be done by pushingthrough the soft bed 121 or simply rotating the non-expanding drill bits109 until hard bed 119 is reached, as illustrated in FIG. 64.

As illustrated in FIG. 65, the latch 10 is released allowing thedrilling assembly to continue drilling through the caisson 107, untilthe desired depth of placement has been reached. It will be noted fromFIGS. 64 and 65 that the height of the caisson 107 is greater than thedepth below water level 120 of the hard rock layer 119. By this meanswater and softer bed 121 do not go back into the caisson protected area.

Once drilling to the required depth is completed, the drilling assembly3 and latch 10 can be removed from the caisson 107, as is illustrated inFIG. 66, and then as in FIG. 67, the next sheet pile 102 joined to theearlier pile 101, and slid into position inside the caisson 107. Thecaisson 107 can then be withdrawn. Then as in FIG. 68, after theinstallation of sheets has progressed, the base hole can be grouted andthe ground level back filled at appropriate time in the installationprocess.

As best illustrated in FIG. 69 the caisson 107 used in FIGS. 63 to 68has a shape to receive 5 drills 109 which are non-expanding drill bit,and will have an excavation p footprint that will allow a sheet pile 102to be installed before the caisson is removed, and after the drillassembly is disconnected and removed from the shaped wall 107.1. It willbe noted that the connection section 125 has a curved wall shape at theends of which are clutches 125.2 and 125.4, and at an intermediatelocation is attached clutch 125.11. It will be noted that he left handmost drill 109, has its left most excavation footprint overlapping theearlier drill footprint 105 associated with installed first sheet pile101.

The connection section 125 is removed immediately before the sheet pile102 is to be inserted as in FIG. 67, in which case the arrangement ofFIG. 70 is adopted where the drilling assembly 3 has been removed andoverleaping footprints 105 and 108 are present, leaving a generally openspace for insertion of the second sheet pile 102 to be inserted in thecaisson 107 by joining respective clutches to sheet 101, as illustratedin FIG. 71.

Then, as in FIG. 72, the caisson 107 is removed, being a step betweenFIGS. 67 and 68, the sheet piles 101 and 102 are sitting in theirrespective excavation foot prints. This will allow the sheet pile 101 tobe grouted into position, while the caisson 107 (or the shaped wall107.1 and the connection section 125) on the surface has been up-ended(that is rotated around a horizontal axis) and the drill assembly 3 hasbeen rotated through 180 degrees around a vertical axis and re-assembledto begin to repeat the steps of FIGS. 63 to 68, this time appropriatelyoriented for the placement of sheet pile 103, as is illustrated in FIG.73. The repeating of steps 63 to 68 will produce a wall segment asillustrated in FIG. 74, whereby the excavation foot print will have beengrouted with grout 122 to secure the respective piles 101,102 and 103into their holes.

Illustrated in FIGS. 75 and 76 is a method and apparatus for installingslidingly interlocking concrete panels 17, which have a male key 17.3and female key or recess 17.4 at opposite ends. The method and apparatusis similar to that described previously in relation to sheet piles, andemploys a generally rectangular open shaped wall 107.1, which can beclosed off by a connection section 125 as illustrated in FIG. 76. Theconnection section 125 has a male key portion 125.11, which will engagerecess 17.4 on an earlier positioned panel 17 to guide the drillingprocess. The drill assembly 3, will include expanding drill bits todrill ahead of the leading edge of the caisson 107, forming excavationfootprint 108 which will overlap with the previously drilled footprint105. Then like the method of FIGS. 63 to 68, the connection section 125is removed, and the next panel 17 can be lowered into positon to join upwith the earlier installed panel 17.

Illustrated in FIG. 77 is another method and apparatus for installing aconcrete panel 17, similar to that of FIG. 75, except that no connectionsection 125 is used. Instead the shaped wall 107.1 simply has an openend in which the right hand side of panel 17 can be located to assistwith the guidance of the drilling process. As the shaped wall 107.1 islonger than in FIG. 75, the footprint 108 will readily overlap with footprint 105, allowing another panel 17 to be installed.

Illustrated in FIG. 78 is a method and apparatus similar to that of FIG.77, except that the concrete panel 17 includes a vertical channel orrecess 140 on each side of the panel 17 near to the end of the panel 17which has the recess 17.4. The recess 140 is a guide recess to receivethe turned in ends of the shaped wall 107.1, and in this way to act toassist in the guiding of the drilling process.

Illustrated in FIGS. 79 to 82 is method and apparatus for installingconcrete panels 17, which are similar to that of FIG. 78, in that at oneend they have vertical guide recesses 140 near one end, but are notinterlocking. Additionally, the drilling assembly 3, does not utilizeexpandable bits, that is drilling occurs only within the confines of theshaped wall 107.1. The drill bits 109 are located at different heightsas shown in FIG. 80, and as in FIG. 81, once the drilling assembly 3 hasbeen removed, allowing a seme shaped panel 17 to be dropped into placein the shaped wall 107.1, abutting the previously inserted concretepanel 17. While no joining of adjacent panel 17 may be done under water,a capping beam 28 as described above, and other joining can be doneabove water level once the shaped wall 107.1 has also been removed as inthe case of FIG. 82, where the panels 17 are ready to be capped.

In the case of each of the methods and apparatus of FIGS. 75 to 82, itis preferred to disconnect the drilling assembly 3 from the shaped wall107.1, and to take out the drilling assembly 3 before dropping in thenext panel 17. This allows the shaped wall 107.1 to keep out soft bed121 from lowing into the drilled hole. However, if the apparatus ofFIGS. 75 to 78 were used to drill into hard ground 119 only, that isthere was not present a soft bed 121, the shaped wall 107.1 and thedrill assembly 3 can be removed together, thereby saving time by savingprocess steps.

In broad terms, as illustrated in FIGS. 83 to 88 is an excavation means3 and a caisson or casing 1 for insertion into soft bed or friableground, with the excavation means 3 being able to excavate inside theopening or opening footprint of said caisson or casing 1. The excavationmeans 3 having a body to mount at least two excavation tools 4.2 or 4.2′so that a series of overlapping excavations 108 will result. Theexcavation means 3 includes a detachable connection to said caisson orcasing 1.

There are one or a multiple number of excavation tools 4.2 or 4.2′illustrated in FIGS. 83 to 88, in this case two, which are distancedfrom each other so that the outside diameter of excavation of the toolsare spaced from each other so that when the body of the drillingassembly 3 is rotated through 180 degrees, the excavation that occursproducing an overlapped excavation footprint 108. However, asillustrated in FIGS. 89 and 90, there can be an odd number of tools 4.2or 4.2′, or as is shown in FIGS. 93 and 94, a single excavation tool. Itwill be noted in the case of the excavation or drilling assemblies 3 ofFIGS. 83 to 88, 90, 91, 93 and 94, that there is located one excavationtool 4.2, 4.2′ close to a side wall of the drilling assembly 3 so as tobe close to the side wall of the caisson or casing 1, but there is alarger spacing to the opposite side wall, from the only or lastexcavation tool 4.2, 4.2′.

The excavation means can be a drilling tool or drilling tool assembly 3.

The excavation means 3 can includes: only expandable drilling bits 4.2;or only non-expanding drill bits 4.2′; or a combination of expandingdrilling bits 4.2 and non-expanding drill bits 4.2′ where the expandingdrill bits 4.2 when expanded have the same outside diameter of thenon-expanding drill bits 4.2′.

There is also described a method of drilling a caisson or casing 1 in asoft bed or friable ground, whereby the method includes the steps of:providing a caisson or casing 1 and an excavation means or assembly 3 asdescribed in the preceding four paragraphs. The method then allows foractivating the excavation means 3 to excavate ground beneath saidexcavation means 3 so as to produce a series of overlapped excavations108 within the opening or opening footprint of the caisson or casing 1,whereby the soft bed or friable ground allows the caisson or casing andthe excavation means or drill assembly to move through it.

Describing now in more detail, illustrated in FIGS. 83 to 85 is anothercaisson or casing 1 and drilling assembly 3, which is similar to that ofFIGS. 1 and 2 described above, except that there are four drill bits 4.2which are expandable, but when expanded, are fully within the internalperiphery of opening footprint of the caisson or casing 1. The bits 4.2are arranged or spaced so that when expanded as in FIG. 84, theyoverlap, and occupy different height positions as depicted in FIG. 85.It will be noted from FIG. 84 that the overlapping of the drilling bits4.2 occupies a substantial surface area of the footprint of the openingof the caisson or casing 1. Whereas when the drill bits 4.2 arecontracted or retracted, they occupy the smaller diameter circles inFIG. 83, and this is reflected illustrated in the side view of FIG. 85.This caisson 1 and drilling assembly 3, is meant to perform its drillingoperation wholly within the confines of the caisson's opening or openingfootprint, and is particularly suitable where soft bed material isencountered or needs to have a for example a pre-case concrete panel 17,as depicted in FIG. 88.

Illustrated in FIGS. 86 and 87 is a caisson or casing 1 and drillingassembly 3, which is similar to that of FIGS. 83 to 85, except that thedrill bits 4.2′ are not expandable. In that respect it is also similarto the caisson and drilling assembly of FIG. 79, except that the caisson1 of FIG. 86 has a fully bounded rectangular caisson or casing and thusdoes not directly act or be guided by the previous panel 17 whereascaisson or casing 107 of FIG. 79 has a shaped wall with an open sectionto interact with the previous panel 17. The drill bits 4.2′ overlap eachso that they are fully within the internal periphery of openingfootprint of the caisson or casing 1. The bits 4.2′ are arranged orspaced so they overlap, and occupy different height positions asdepicted in FIG. 85. It will be noted from FIG. 86 that the overlappingof the drilling bits 4.2′ occupies a substantial surface area of thefootprint of the opening of the caisson or casing 1.

While not illustrated, if desired, the caisson 1 can have on its outerwall a shaped formation to engage the keyway formed at the end of thepreviously installed panel 17, so that the previous panel can guide thecaisson or assist in locating it. Even without such a shaped guideformation, the abutting of the outside of eth caisson 1 with the end ofthe previously installed panel 17, helps to space and/or locate thecaisson 1 while drilling occurs.

While the embodiments of FIGS. 83 and 86 show expandable bits 4.2 andnon-expandable bits 4.2′, it will be understood that a combination ofexpandable and non-expandable can be utilized, providing the outerdiameter of the expandable bit is equal to or approximately equal tothat of the non-expandable bit's diameter.

The caisson or casings 1 and drilling assemblies 3 of FIGS. 83 and 86will both produce an excavation foot print 108 as illustrated in FIG.88, which is sized so as to receive a pre-cast concrete panel 17therein, which is spaced from the earlier panel 17 on the left of FIG.88. Once the caisson 1 is removed the space between adjacent panels 17can be grouted or interlocking join piece inserted into the gap betweenthe panels 17 to complete the shoring wall, as described above withrespect to FIG. 13 to FIG. 16.

In respect of the embodiments of FIGS. 83 and 86, a typical outerdiameter of the drill bits 4.2 when expanded or the bits 4.2′ is 290 mm,with the first centre of rotation being spaced about 15) mm from theinside end wall of the caisson or side wall of its opening. Whereas thespacing between centers of rotation of the drill bits are about 208 mmapart, with the caisson 1 having an opening, or opening footprint, ofabout 940 mm by 315 mm, so as to provide an excavation footprint 108which will receive a panel 17 of 175 mm×850 mm.

It will be noted that the improvement described above with respect toFIGS. 41 and 42 can be applied to the embodiments of FIGS. 83 and 86, inthat a drilling assembly having two appropriately spaced drill bits 4.2or 4.2′, for locating at the first and third positions from the left ofFIGS. 83 and 86 can be provided, and so that once drilling of two holeshas occurred the drilling assembly can be removed and rotated around avertical axis through 180 degrees, and then the holes at the second andfourth positions from the left drilled.

The above described embodiments relate to installing pile elements suchas a sheet, or panel or a pile wall element. The same method and/orequipment as described above can be used, as illustrated in FIG. 97,with a pile element such as a pile modular wall elements 17, 17A and17B, and their related sliding engagement system. These can be used as amodular wall elements per se, or if desired can be used to form anin-situ concrete formwork and panel, and utilizes a similar method tothat described above in respect of FIG. 75 to FIG. 78, in relation tothe embedment of the pile element. Once all the pile modular wallselements 17 have been positioned then these form a pile wall or they canhave appropriate reinforcing added and then filled by means of pumpedgrout, concrete or fibre reinforced concrete, or poured gravel to createthe wall, with the formwork remaining in situ. Such modular wallelements and pile elements 17 are described in U.S. Pat. Nos. 7,628,570and 8,033,759 which are incorporated herein by reference.

Thus the method of drilling and placement in respect of the embodimentillustrated in FIG. 97 comprises a first pile modular wall element 17(or a series of 2 or more such elements joined together) is positionedwithin the boundary 105 of the ground disturbed or drilled by thedrilling or excavation assembly 3 (not illustrated) which also positionsa caisson 107, allowing the first pile modular wall element 17 to thenbe located into place in the boundary of the series of overlapping holes105. Then, a connecting section or piece 125, having two rear clutches125.11 to engage the respective forward clutches of the first pilemodular wall element 17, and forward clutches 125.2 and 125.4 to engagethe clutches A and B respectively on the caisson 107, are assembled tothe clutches A & B on the caisson 107 to which has been pre-assembledthe drilling or excavation assembly 3 (not illustrated). The connectingsection or piece 125 by means of rear clutches 125.11 is fed into theforward clutches of the end of first pile modular wall element(s) 17 andthe forward-most first pile modular wall element 17 will be clear of thearc of the cutter which is digging the rear section of boundary 108,with the assembly of drilling assembly 3, caisson 107 being guided inits ground engagement by the forward-most first pile modular wallelement 17. When desired depth is achieved the drilling or excavationassembly 3 (not illustrated) is removed from the caisson 107, and so toois the connecting piece 125, allowing the rear clutches of pile modularwall element 17A to first be engaged with the forward most clutches ofelement 17 allowing the element 17A to be driven into place by either abucket of an excavator or hammered into place. Once the element 17A isin place, then element 17B can be likewise installed. Alternativelyelements 17A and 17B (or more) can be pre joined, and then driven intoplace as a sub-assembly. This system is then repeated until an assemblyof pile modular wall elements 17 of desired length is formed. The pilemodular wall elements 17A and 17B are represented in broken line-work asthey are not positioned until the connecting piece 125 has been removedfrom engagement with the forward most end of the element 17.

During this assembly process, the lowermost end of the pile modular wallelements 17 are held in place by means of mud or other introducedsediment, while the upper ends are held in place by a locating falseworkor temporary support or formwork which braces and secures the upper endsto their desired location. In such location if desired concrete can alsobe poured. This locating false work or formwork can also be used to tiein and/or form the capping beam 28, and to tie in the interconnectinganchors 32, 32.1 and 32.2 as seen in FIG. 18.2.

While the above description of FIG. 97 indicates the use of theconnection section 125 having two rearwardly directed clutches 125.11,if desired, a modified arrangement can be utilized, such as thatillustrated in FIG. 98, where an improved TRULINE modular wall elementis extruded or formed with side located internal grooves or clutches17.33. By having a purpose built caisson or casing 107 for the firstwall element 17 (or assembly of elements 17) to be inserted, and havinga second purpose built caisson or casing 107 as illustrated in FIG. 98,the wall of which terminates at each end with a respective inwardlydirected clutch A and B, so as to be located outside the diameter of thecutters, will engage the clutches 17.33 on the, or the forward-most,wall element 17. By this means, the caisson 107 and drilling assembly 3(not illustrated) can be guided in its drill process by the first wallelement 17 or assembly of wall elements 17, and once the drillingassembly is retracted from the caisson 107, the space within the caisson107 is able to received elements 17A and 17B either sequentially assingle units, or as an assembly of wall elements. The element 17Aconnecting to element 17 in FIG. 98, can be like one used in FIG. 97,providing the front most element used is has side clutches 17.33 as isthe case with element 17 of FIG. 98. An additional advantage of thegrooves or internal clutches 17.33 is that the overall appearance of thewall element 17 is substantially unchanged.

As illustrated in FIG. 99, a wall element 17, similar in profile to theTRULINE modular wall element, can be made having external clutches 17.35formed on the outside walls of the wall element, near to one end. Theembodiment of FIG. 99 will operate in the same manner as that describedwith respect to FIG. 98, and like it, the external grooves or clutches17.35. By also having a purpose built caisson or casing 107 for thefirst wall element 17 (or assembly of elements 17) to be inserted, andhaving a second purpose built caisson or casing 107 as illustrated inFIG. 99, the wall of which terminates at each end with a respectiveclutch A and B, so as to be located outside the diameter of the cutters,will engage the respective clutches 17.35 on the, or the forward-most,wall element 17. By this means, the caisson 107 and drilling assembly 3(not illustrated) can be guided in its drill process by the first wallelement 17 or assembly of wall elements 17, and once the drillingassembly is retracted from the caisson 107, the space within the caisson107 is able to received elements 17A and 17B, either sequentially assingle units, or simultaneously as an assembly of wall elements. Thesubsequent element 17A connecting to element 17 in FIG. 99, can be likeone used in FIG. 97, providing the front most element used has sideclutches 17.35 as is the case with element 17 of FIG. 99.

The wall elements 17 of FIGS. 97, 98 and 99 provide a retaining wallelement for use in controlling land erosion in contact with water whichhas self-supporting polymeric construction, each element having avertical longitudinal interior channel 17.51 disposed therein enclosedby at least three sides 17.52. If desired a fourth side can be providedand also if desired an intermediate wall can be provided, or a fasteningmeans to allow an intermediate wall to be assembled thereto.

Each of the modular wall elements 17 have a pair of opposed ends whichterminate with one or more fastening means 17.53, in this case 2 perend. Each of the modular wall elements 17 connect to a like or similarmodular wall element 17 by mating engagement of the at least onefastening means 17.53 on one first wall element 17 with at least onefastening means 17.53 on the at least one second wall element 17A, thefastening means 17.53 being an engageable clutch or J-shaped hook.

The embodiments of FIGS. 98 and 99 differ from that of FIG. 97 in thatat least one of the wall elements includes in or on at least one of afront wall 17.54 and/or rear wall 17.55, an elongated fastening means17.33, 17,35 allowing the at least one wall element to connect to theends A and B of a wall or walls of a casing or caisson 107 and/or adrilling element 3, which will be used to drill and/or keep clear avolume in which the element 17 or 17A or elements 17 and 17A will beinstalled in an underwater location.

The fastening means 17.35 on the front wall 17.54 and/or the rear wall17.55 are illustrated in FIG. 99 as being an externally arrangedengageable clutch or J-shaped hook; whereas in FIG. 98 the fasteningmeans 17.33 are illustrated as being an internally arranged engageableclutch or groove able to receive a J-shaped hook.

The wall elements 17, 17A 17B of FIGS. 97, 98 or 99 are formed orconstructed, by virtue of its wall formation, features, shape and/orthickness, to function as a structural wall when it is in a hollowcondition.

Additionally, wall elements 17, 17A 17B of FIGS. 97, 98 or 99 areinitially hollow and when joined and assembled with like or similarelements, are then used as an in-situ formwork and subsequently filledwith concrete, cement or grout to form a finished structural wallconstruction.

If three walls 17.52 are present on each element 17, 17A or 17B, then atleast one end cap having a fastening means to attach to the element canbe used so as to close off the otherwise open volume of the end sectionof the element.

Illustrated in FIGS. 100 to 109 is a combination drilling and reamingtool 3 for direct use with the wall elements 17, 17A and 17B of FIGS. 97to 99, that is where a caisson or casing 107 is not unlisted.

Illustrated in FIG. 100 is a modular wall element 17A engaging a likemodular wall element 17, each being such as a TRULINE modular wallelement, into which is positioned a drilling and/or reaming assembly 3which has a rotating non-expandable drill bit 4 which is at the base ofa drive shaft 6. At a location above the drill bit 4 is a pair ofreaming elements 3.1 (on opposite ends of a cable or such like) which isshown as being bent in FIG. 100, so that its ends 3.11 are downwardlydirected while the assembly 3 is exiting the wall element 17A as thedrill assembly 3 is pulled through after drilling and reaming has beencompleted. The pairs of reaming elements 3.1, (or multiple pairs ofelements as there can be a multiple pairs of the reaming elements 3.1 atdifferent heights on the shaft 6 as described in more detail below) canalso have their ends 3.11 upwardly directed as the drilling assembly 3is pushed through the wall element 17A. Before being inserted into thewater, on a land location near to the installation site, whilst stilllaid flat onto ground, a drilling assembly 3 and a modular wall elementare assembled together so that the one or more pairs of reaming elements3.1 and drill bit 4 are situated proud of the lower rim 17.33. It is inthis state that they are locked together by a pin or other mechanicalreleasable interconnecting means. When so locked together, they can behoisted together, with the lowest point of the clutches 17.53 beingengaged with the clutches of the earlier installed wall element 17, andthen pushed down until the drill bit engages ground to be drilled and/orreamed. When drilling and/or reaming is complete, and the wall element17A is at a desired depth, the releasable mechanical interconnection isreleased, and the clutches of the interconnnected elements 17 and 17Acan then be locked together preventing their separation, and at thispoint, the drilling and reaming assembly 3 can be withdrawn from thewall element 17A.

The respective pairs of reaming elements 3.1 will have their maximumlength or diameter when rotating, determined by the geometry as depictedin FIG. 112, and this will be described in detail below. The reamingelements 3.1 or pairs of reaming elements 3.1 are preferably made fromhelically wound stranded cables of mild steel of approximately 10 mm to50 mm in outside cable diameter, with the preferred being of the orderof 20 mm. It will be understood that this dimension will need to be acompromise between the amount of flexibility required of the reamingelements 3.1 as it is pulled through the wall element 17A aftercompletion of the drilling and reaming process, as well as other factorssuch as the size of the wall element 17A, compared to the poweravailable to rotate the drilling and/or reaming assembly 3, and even thepressure of pumping of the drilling fluid.

The helically wound spiral strands at the respective ends 3.11 arewelded together to prevent the individual strands from unravelling fromthe cable during reaming operations. The outside shape of the cable,being “shaped” or “profiled” due to the helically wound nature of thecable, acts like a series of radially located teeth, which will engagethe ground surface to be reamed, when the drilling assembly is rotatedat the order of 50 to 70 RPM, or a higher or lower speeds depending uponthe hardness of the ground which the reaming tool 3.1 is to engage. Thedrilling bit 4 can be an expanding bit but its size is determined solelyon its ability to move into and out through the modular wall element 17.When the drill bit 4 is engaging the ground to be drilled and reamed,its main role is to guide the reaming elements 3.1 in their downwardjourney. As will be described later, the drill and reaming assembly 3,is guided in its motion downward, by the modular wall element 17A, whichwill downwardly slide along the clutch of an earlier positioned likemodular wall element 17.

As illustrated in FIGS. 102 and 103, which are underneath views of thearrangements of FIGS. 100 and 101 respectively, the reaming tool 3.1shows the ends 3.11 as being multi-stranded, and each strand is initself a multi-stranded cable element. When the ends 3.11 are free ofthe confines of the modular wall element 17A, they expand to their fulllength, or at least will do so, when rotated by the drive shaft 6 at 50RPM to 70 RPM.

The reaming elements 3.1 can be considered to make up a single toolcalled a reaming bit having four or six expanding parts, depending onhow many cable or spring steel sections are utilized.

From FIGS. 102, 103 and 112, it will be noted that the drill bit 4 andpairs of reaming elements 3.1 have their centre of rotation 4.15, beingalso the centre of rotation of the drive shaft 6, is located off-centrerelative to the length of the modular wall element 17A, as bestexemplified by the dimension OD1 in FIG. 112, which shows the offsetfrom the physical centre of the overall length of the element 17A, orthe dimension OD2 which shows the offset from the structural centre ofthe wall element 17A. From FIG. 103 it will be noted that theextremities of ends 3.11 when rotated around the axis 4.15 extend pastthe free clutches 17.53 at the forward-most end of the modular wallelement 17A being illustrated by distances F1 and F2, but also will notintersect or collide with the clutches 17.53 on the modular wall element17 already or earlier positioned into the ground, by distances C1 and C2and which clutches 17.53 act as a guide for the modular wall element 17Abeing inserted and thus the drilling and reaming assembly 3. It ispossible that the off-set distances OD1 and OD2 are in fact the samedimension, as a scale representation of the modular wall element 17A isnot provided in this document.

To achieve this off-centre arrangement, the dimensions F1, F2, C1, C2and S1 and S2 will be of the order of 5 mm to 20 mm and will bedependent upon several factors including the tolerances in the drillstring, the type of ground being drilled, which may cause the bit towander off line. Once the drill centre is identified, then one or moreguide plates 3.23 are utilized along the length of the modular wallelement 17A, so as to locate and keep the centre of rotation 4.15 of thedrill bit 4, reaming tool 3.1 and the drive shaft 6 at the correctpositional arrangement to prevent the collision of the reaming tool 3.1with the clutches of the earlier positioned modular wall element 17, andyet to excavate ahead of the clutches 17.53 at the forward-most end ofthe modular wall element 17A being positioned or inserted. This is bestillustrated in FIG. 112, where a single drilling and reaming toolassembly 3, having one centre of rotation 4.15, will excavate acylindrical excavation 108, which will overlap with the previouslyformed excavation 105, but which will not overlap with the forward-mostpoint of the forward clutches 17.53 of the earlier positioned modularwall element 17. As the reaming tool is below the lower rim 17.33 ofmodular wall element 17A, there will be no interference from the rearend clutches of modular wall element 17A which engage clutches 17.53 ofmodular wall element 17 positioned earlier.

The guide plates 3.23 are shaped so as to provide a good sliding fitwith the internal shape of the modular wall element 17A, and there ispreferably approximately 2 mm to 5 mm of clearance between the outsidesurface of the guide plate 3.23 and the internal surfaces of the modularwall element 17A. Thus as illustrated in FIG. 109, the end 3.231 isshaped so that the clutches and formations provided will not interferewith the sliding movement (or vica-versa), and at an intermediatelocation grooves 3.232 are provided to accommodate the T-shaped joiningformations on at the centre of the modular wall element 17A. Asillustrated in FIG. 108, the guide plate 3.23 includes a cylindricaljournal bearing 3.233 to assist the drive shaft 6 in its rotation. Thelower guide plate 3.23 has an upwardly extending portion 3.234 whichextends upwardly for optional connection to a similarly constructedintermediate guide plate, and so on up through the modular wall element17A, until the upper end is reached at which upper end the drill motor3.20 is mounted. The number of guide plates 3.23 will be dependent uponthe length of the modular wall element 17A.

As an alternative to the provision of guide plates 3.23, the drillingand reaming assembly 3 can be preassembled, as illustrated in FIGS. 114and 115 into a housing arrangement which sits within and slides withinthe wall element 17A. The housing arrangement or mandrel as illustratedcan be either of a solid construction or of a hollow construction. Themandrel has a shaped body 3.13, which has a similar outer peripheralshape, as best illustrated in FIG. 115, to that of the guide plates3.23, whereby a sliding fit into the modular wall element 17A willresult. The drilling and reaming assembly 3 of FIGS. 114 and 115 has amotor 3.20 below which is mounted a drilling fluid or water swivel 3.241to which connects the flushing line 3.24. Below the swivel 3.241 is thedrive holder 3.21 which will fit over the upper rim of the modular wallelement 17A, and which can be releasably locked together by a pin or abolt or any appropriate means, once the mandrel body 3.13 is insertedwithin a wall element 17A.

Like drilling and reaming assembly 3 of FIGS. 100 to 109, the drillingand reaming assembly 3 as best illustrated in FIG. 115, the assembly 3has a drive shaft 6 which extends from the motor 3.20 to the drillingbit 4 and reaming bits 3.1, as well as a horizontal flushing fluidoutlet port 6.2 when the assembly 3 is vertical, or which can bedescribed as ejecting flushing fluid at an angle of approximately 90degrees to the longitudinal axis of the drive shaft 6.

Additionally, as shown in cross section in FIG. 115, the shaped body3.13 like the guide 3.23, have their respective ends 3.231 beingsimilarly shaped, so as to be slidably received by the wall element 17A,when inserted into the element 17 and be clear of the wall formationsand clutches. The difference between guide 3.23 and body 3.13 is thatthe end 3.231 of the body 3.13 extends the full length of the body asbest illustrated in FIG. 114. Similarly, the location groove 3.232 onthe opposed sides of the body 3.13 extend the full length of the body3.13 and are shaped similarly to the grooves 3.232 of the guides 3.23,so as to be slidably received by the intermediate T-shaped joiningformations of the wall elements 17A. Also like the guide 3.23, the body3.13 is sized so that there exists approximately 2 mm to 5 mm ofclearance between the outside surface of the body 3.13 and the internalsurfaces of the modular wall element 17A or 17.

As illustrated in FIGS. 114 and 115 the drilling and reaming assembly 3has two pairs of reaming elements 3.1 which can be held in “bits” in thedrive shaft 6, or as part of separate bits which are added to the baseof the drive shaft and to which the drill bit 4 is also attached. Therespective two pairs of reaming elements 3.1 are formed from a spiralwound cable as described above or they can be made of spring steel baror formed with parts constructed of cable or spring steel, to clear anexcavation 108, as in the earlier embodiment. Like the earlierembodiments, there can be only a single pair of reaming elements 3.1,which will provide the most dynamically stable arrangement, or ifdesired there could be only a single reaming element (not a pair of)being only a single arm extending in one direction only from the driveshaft 6. Alternatively there can be more than two opposed pairs, or morethan one single arm reaming element, located at different heights on thedrive shaft 6, and also being angularly spaced from the adjacent singlearm reaming elements.

The drilling and reaming assembly 3 of FIGS. 114 and 115, is preferablyof a length to suit the length of the wall element 17A. However, ifdesired the body 3.13 can be made in multiple joinable segments or partsso that segments of the body 3.13 can be removable or receive more likesegments to increase or decrease the length of the body 3.13 and thedive shaft 6.

As is illustrated in FIGS. 104 and 105, the drilling and reamingassembly 3 has a motor 3.20 such a hydraulic motor or the like. Aflushing line 3.24 connects via a rotating joint (not illustrated- seeitem 3.241 in FIG. 114 for a similar rotating joint) with the driveshaft 6 longitudinally extending flushing hole 6.1, which as is visiblein FIG. 106, descends down to the base of the shaft 6 and through thedrill bit 4, so as to provide horizontally directed flushing streams6.3, from horizontal passages 6.2 at the base of the drive shaft 6 or inthe drill head 4. The preference is that the drilling fluid or flushingmedium utilized exits the drill assembly 3 at the lowermost point, andas such this will be horizontally through the drilling head 4. This willensure delivery of the fluid material direct to the undisturbed portionof the area being excavated. The flushing system formed with drill fluiddelivery line 3.24-not shown connected) can be used to pump water, mud,air, polymer compositions, bentonite or any other appropriate flushingor drilling compound, as will be known to those skilled in the art.Preferably the flushing system will be pressurized to of the order of 50to 500 PSI.

Preferably the section of the drilling and reaming assembly 3, betweenthe drive holder 3.21 and the lower guide plate 3.23, is of a modularconstruction, so that “modules” of drilling and reaming sections can beadded/assembled or removed/disassembled from the assembly 3, so thatdifferent lengths of modular wall elements 17A can be positioned. Thismodular nature of the drilling and reaming assembly 3 can be achieved byscrew thread connections between the modular components.

The upper end of the assembly 3, below the motor 3.20 includes a driveholder 3.21 which has an undercut channel portion 3.22 into which can bereceive the upper rim of the modular wall element 17A to be inserted.The combined action of gravity active upon the upper rim of modular wallelement 17A, and the drilling and reaming action of the drilling andreaming assembly 3, ensures that the modular wall element 17A willdescend to the desired depth into the ground being drilled and reamed.It is not expected that the drive holder 3.21 will have to transmitpercussion and/or vibratory force to the wall element 17A, but it can beconfigured so as to be readily adapted to do so.

The above description has the reaming elements 3.1 being madeexclusively from sections of cable. However if desired, the reamingelements 3.1 need only have a cable section at the location wherebending is to be present. Thus the reaming tool 4.1 need only need bepartially made from a cable. Additionally, the reaming element 3.1 couldbe made as a spring steel reaming element or have a spring steelportion, to provide the flexibility and resilience needed to draw thereaming elements 3.1 out through the wall element 17A once reaming anddrilling is completed.

Another alternative is that the reaming elements 3.1 can be made as anexpanding and contracting reaming bit, whereby through an arrangement oflevers and mechanisms, the reaming bit can be contracted for withdrawalpurposes. Additionally or alternatively, the reaming elements 3.1 can beof the sort that expand by rotation or otherwise can be hydraulicallyactivated.

As best illustrated in FIG. 104, the reaming elements 3.1 can be made upof a multiple of reaming elements 3.1, 3.1A, 3.1B and 3.1C, so that theyare radially spaced on the drive shaft 6, as best illustrated in FIG.107, at approximately 45 degrees apart in plan view. Preferably thehelically wound cable elements which form the reaming elements 3.1, areheld immoveable and centred relative to the drive shaft 6 by means of agrub screw or bolt which engages the cable at 90 degrees, and secures itinto place. This allows ready replacement of worn cable elements 3.1. Ifready replacement is not required, then the elements 3.1 can be weldedor crimped into place on the drill shaft.

The cable length which forms the elements 3.1 ensures that there issufficient flexibility and resilience, so that the ends 3.11 will bendand fit into the cavity of the modular wall element 17A, when the drilland/or reaming assembly 3 is being inserted into and/or withdrawn fromthe modular wall element 17A. In the region of the section of driveshaft 6 where the reaming elements 3.1 to 3.1C are located, the internalpassages which will carry the drilling fluid have a greater crosssectional area than the reaming tool diameter so that when theyintersect and the cable installed, there is a path for drilling fluidunder pressure to pass around the cable and continue on to thehorizontal outlets.

The length of the cable section selected for the pairs of reamingelements 3.1 is based on the location of the centre or axis of rotationof the drilling and reaming bits being at an off-centre location, asbest illustrated in FIG. 112, where the extremities of the drillingand/or reaming bits have a locus or rotation envelope or excavationwhich clears the clutches 17.53 of a previously installed modular wallelement 17, and which locus or rotation envelope or excavation extendspast the forward or opposite side clutches 17.53 of the wall element 17Abeing installed.

It will be understood that the very first wall element, for examplemodular wall element 17, will be installed by the same drill assembly asused by the second wall element 17A, except that the reaming bit willhave longer cable sections for the pairs of reaming elements 3.1, sothat from the centre of rotation or rotation axis, the extremities ofthe ends 3.11, when fully extended will have a locus, or rotationenvelope, or excavation footprint, which clears the forward and rearwardclutches 17.53 of the modular wall element 17 being first installed. Itis for this reason that having the cable or tool holder being forexample a grub screw can be highly advantageous as multiple drilling andreaming assemblies 3 is not required.

FIGS. 100 to 109 and 112, illustrate a wall element system and drillingand/or reaming assembly 3 which has a single drilling and reaming driveshaft 6 and rotation axis 4.15. Illustrated in FIGS. 110 and 111, arethe geometries to achieve a similar result as that illustrated in FIGS.100 to 109 and 112, but with two rotation centers, where the drillingand reaming assembly 3 has two drive shafts 6, with bit 4 and reamingtools 3.1 on one shaft and located at a different height to the othershaft.

While the drilling and/or reaming assemblies 3 of FIGS. 100 to 115 havea motor 3.20 located outside of the wall element 17A, it will be readilyunderstood that the motor 3.20 can be located inside the wall element17A, but must be of a size that allows for the extraction of the motorand drilling and/or reaming bits through the wall element 17A.Additionally the motor can be at an upper location within the wallelement 17A, or at an intermediate location or at a lower locationwithin the wall element 17A. Further the motor 3.20 could be locatedbelow the wall element 17A, but this is expected to require the drillingand/or reaming of deeper excavations, than that expected with the otherlocations described above.

Illustrated in FIG. 113 is a caisson or casing system, similar to thatof FIG. 97, which utilizes a connection piece 125 which does not engagethe clutches 17.53 on the first positioned wall element 17. Instead theconnection piece 125, which is removeable from the caisson or casing107, due to rearward extensions 125.3 will prevent the caisson or casing107 from moving in a direction up or down the page as illustrated inFIG. 113, and by the exertion of a relatively small force in thedirection from the caisson or casing 107 towards the wall element 17,the caisson or casing, by means of the outside face of the connectionpiece 125 sliding over the outer points of the clutches 17.53, will beable to achieve a sufficient guiding action of the drilling or drillingand reaming assembly 3 to sink the caisson or casing 107 into andoverlapping excavation 108 into the ground.

VI. LEGENDS

FIGS. 1.1, 1.2, 1.3, 2.1, 2.2, 2.3, 3.1, 3.2, 3.3, 4.1, 4.2, 4.3, 5 to10, and 13 to 22 have the following feature legend (not all are listed):

-   1—caisson;-   1.2—structural core cast inside a caisson to be left in situ;-   2—caisson leading edge;-   2.1—gap between caisson/casing and the body of the drilling    assembly;-   3—excavation drilling assembly;-   4—drill bit retracted;-   4.1—drill bit extended or expanded;-   4.2—drill bit extended or expanded;-   4.3—drill bit extended or expanded;-   5—rotation motor;-   6—drive shaft;-   7—hydraulic flow divider;-   8—bearing housing with flushing hole;-   9—base of bearing with flushing hole;-   10—latch assembly;-   10.1—latch body;-   10.2—latch pivot stationary relative to drill assembly 3;-   10.3—latch pivot moveably pivoted and mounted to lift flange 12.1;-   10.4—mounting plate attached to drill assembly 3;-   11—recess in caisson to accept latch;-   12—lifting assembly or chain;-   12.1—lifting flange or eye;-   12.2—compression spring;-   12.3—mounting bolt;-   12.4—mounting washer;-   12.5—mounting nut;-   13—hydraulic hoses;-   14—flushing hoses;-   15—flushing hole in drill bit;-   16—normal direction of rotation to keep retracted;-   17—structural panels;-   17.1—vertical gap between adjacent panels;-   17.2—pre-existing structural panel in the ground;-   18—stocking;-   19—grout line;-   20—grout key;-   21—grout tube for toe grouting;-   22—toe grout;-   23—penetration for dowel;-   24—hard ground or rock;-   25—hole drilled into hard ground or rock;-   26—dowel;-   27—grout line for down penetration hole;-   28—capping beam;-   28.2—existing capping beam;-   29—apertures for capping beam reinforcement bars;-   30—reinforcement bars inserted into apertures in the panel;-   31—reinforcement bars cast into the panel;-   32—anchoring ties;-   32.1—extended portion of an anchoring tie linking new and existing    capping beams;-   32.2—anchoring tie to an existing capping beam;-   1′—trailing caisson;-   33—displaced plasticized ground matter;-   34—trailing edge projection for end-to-end attachment between    caissons;-   35—leading edge projection for end-to-end attachment between    caissons;-   36—groove in the leading edge projection to accommodate the trailing    edge projection of an adjacent caisson;-   38—rope used in a pulling operation to lower the caisson;-   40—pulley used in a pulling operation to lower the caisson;-   S—parting plane between sections of a caisson;-   100—hydraulic or pneumatic cylinder.

FIGS. 23 to 50 include features from following legend (not all arelisted):

-   101—first sheet to be placed;-   102—second sheet to be placed;-   103—third sheet to be placed;-   104—clutch;-   105—boundary of the ground disturbed while placing the first sheet;-   106—connecting section of the caisson;-   107—caisson;-   108—boundary of the ground disturbed by the tool or excavation    footprint;-   109—expandable drills;-   110—tool holding the expandable drills;-   111—blank connecting piece;-   112—sheet to be connected too;-   113—last full sheet placed;-   114—fabricated connecting piece;-   115—boundary of the ground disturbed placing sheet 112;-   116—boundary of the ground disturbed placing sheet 113;-   117—layer of hard ground the sheet pile must pass through;-   118—ground level;-   119—hard seabed;-   120—water level;-   121—soft seabed;-   122—grout filling the drilled hole;-   124—caisson half;-   125—connecting section or piece;-   126—connecting pin/bolt;-   133—expanding drill in retracted condition;-   134—expanded diameter being drilled;-   135—adjacent diameter to be drilled next;-   136—holes previously drilled;-   137—hydraulic motor for powering drill;-   138—ground level;-   139—conventional sheet pile driving implement or equipment;-   140—cast locating groove;-   XX—axis in plan through the clutches of the sheets to be installed;-   YY—minor axis in plan through the caisson 107 and the tool 3.

Where ever it is used, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

It will be understood that the invention disclosed and defined hereinextends to all alternative combinations of two or more of the individualfeatures mentioned or evident from the text. All of these differentcombinations constitute various alternative aspects of the invention.

While particular embodiments of this invention have been described, itwill be evident to those skilled in the art that the present inventionmay be embodied in other specific forms without departing from theessential characteristics thereof. The present embodiments and examplesare therefore to be considered in all respects as illustrative and notrestrictive, and all modifications which would be obvious to thoseskilled in the art are therefore intended to be embraced therein.

1. A retaining wall element or element of a formwork system for a groundor underwater location, the retaining wall element or element of aformwork system having a shaped wall which is open for a predeterminedlength, which is adapted to receive and connect to an excavation meanswithin the confines of the retaining wall element or element of aformwork system.
 2. A retaining wall element or element of a formworksystem as claimed in claim 1, wherein the shaped wall has its free sideseach having a clutch, and a connecting section which closes theretaining wall element or element of a formwork system.
 3. A retainingwall element or element of a formwork system as claimed in claim 2,wherein the connection section has a wall portion with a mating clutchto join with the clutches at the wall sides of the retaining wallelement or element of a formwork system.
 4. A retaining wall element orelement of a formwork system as claimed in claim 2, wherein theconnection section is formed from one or more wall portions havingclutches on it or them or can also include at least one element clutchor join formation which is adapted to engage another retaining wallelement or formwork element previously inserted in the ground orunderwater location.
 5. A retaining wall element or element of aformwork system as claimed in claim 2, wherein the connection section isa sheet pile, panel, open section retaining wall element or formworkelement or is formed and/or shaped as a sheet pile, panel, open sectionretaining wall element or formwork element so as to function as a sheetpile, panel, open section retaining wall element or formwork element,which is adapted, in use, to be separable from the retaining wallelement or element of a formwork system.
 6. A retaining wall element orelement of a formwork system as claimed in claim 2, wherein theconnection section has at least one clutch, which is adapted to connectto at least one clutch of the retaining wall element or element of aformwork system.
 7. A retaining wall element or element of a formworksystem as claimed in claim 6, wherein the connection section has atleast one element join formation or clutch which is adapted to engage apreviously inserted retaining wall element or element of a formworksystem or clutch thereof.
 8. A retaining wall element or element of aformwork system as claimed in claim 7, wherein the at least one elementmating join formation or clutch on the connection section, by beingadapted to engage an retaining wall element or element of a formworksystem or clutch on one of these previously inserted in the ground orunderwater location, is adapted to act as a guide to guide the retainingwall element or element of a formwork system, and an excavation meanscombined therewith, as excavation occurs.
 9. A retaining wall element orelement of a formwork system as claimed in claim 7, wherein said atleast one element mating join formation or clutch on the connectionsection is at least two such element mating join formations or clutches.10. A retaining wall element or element of a formwork system for use incontrolling land erosion in contact with water which wall element orelement of a formwork system comprises: self-supporting polymericconstruction, each having a vertical longitudinal interior channeldisposed therein enclosed by at least three sides; each of said elementshaving a pair of opposed faces to which are connected one or morefastening means; each of said elements connected by mating engagement ofthe at least one fastening means on one first element with at least onefastening means on said at least one second element, said fasteningmeans being an engageable clutch or J-shaped hook; characterized in thatat least one of said elements includes in or on at least one of a frontwall and/or rear wall, an elongated fastening means allowing said atleast one element to connect to the ends of a wall or walls of a casingor caisson and/or a drilling element, which will be used to drill and/orkeep clear a volume in which said element or elements will be installedin an underwater location.
 11. A wall element as claimed in claim 10,wherein said fastening means on said front and/or said rear wall is anexternally arranged engageable clutch or J-shaped hook.
 12. A wallelement as claimed in claim 11, wherein said fastening means on saidfront and/or said rear wall is an internally arranged engageable clutchor groove able to receive a J-shaped hook.
 13. A wall element as claimedin claim 12 which further comprises at least one end cap having afastening means to attach to said element.
 14. A wall element as claimedin claim 10, wherein said element is constructed by its wall formationshape and/or thickness to function as a structural wall when it is in ahollow condition.
 15. A wall element as claimed in claim 10, whereinsaid wall element is initially hollow and when joined and assembled withlike or similar elements, is then used as an in-situ formwork andsubsequently filled with concrete, cement or grout, or filled withgravel to form a finished structural wall construction.
 16. Anexcavation means for use with an open section retaining wall element orelement of a formwork system installed via a caisson or casing so as toexcavate in front of the leading edge of a retaining wall element orelement of a formwork system, said excavation means having a body tomount at least one excavation tool so that the at least one excavationtool is spaced from a wall of the retaining wall element or element of aformwork system, or if multiple tools are present they are spaced fromeach other so that the outside diameter of the at least one excavationof the tools are spaced from each other, said excavation means alsoincluding at least one reaming portion which is formed from a section orlength of cable.
 17. An excavation means as claimed in claim 16, whereinsaid excavation means includes a flushing passage which discharges in adirection at approximately 90 degrees to the axis of rotation of theexcavation means.
 18. An excavation means as claimed in claim 16,wherein said excavation means includes a flushing fluid system ordrilling fluid system which operates to pump drilling fluid from saidexcavation means or a portion there of, at a pressure of the order of 50psi to 500 psi.
 19. An excavation means as claimed in claim 16, whereinsaid excavation means includes a shaped body or shaped guides whichlocate said excavation means to excavate relative to or along apre-determined axis, which axis is located at an off-centre locationrelative to the footprint of retaining wall element or element of aformwork system.
 20. An excavation means as claimed in claim 19, whereinsaid off-centre location provides the extremities of a locus or rotationenvelope or excavation which clears the clutches of a previouslyinstalled retaining wall element or element of a formwork system, andwhich locus or rotation envelope or excavation extends past the forwardor opposite side clutches of the retaining wall element or element of aformwork system being installed.
 21. An excavation means as claimed inclaim 16, wherein said excavation means includes a segmentedconstruction allowing the assembly to be increased or decreased inlength to suit different lengths of said caisson or casing or opensection retaining wall element or element of a formwork system beinginstalled.
 22. An excavation means as claimed in claim 16, wherein saidexcavation means is one of: a jet grouting tool; a drilling tool; areaming tool; a drilling and reaming tool.